Using the balanced equation:
cu(no3)2(aq)+2koh(aq) —> cu(oh)2(aq)+2kno3(s)
what is the possible yield of the solid precipitate in grams? 207.3 g of
copper (i) nitrate reacts with 86.7 g of potassium hydroxide.

Answers

Answer 1

The possible yield of the solid precipitate in grams is 49.2 g. The balanced equation shows that 1 mole of copper (I) nitrate reacts with 2 moles of potassium hydroxide to form 1 mole of copper (II) hydroxide and 2 moles of potassium nitrate.

To calculate the yield of the solid precipitate, we need to determine the limiting reactant. First, we convert the given masses of copper (I) nitrate and potassium hydroxide to moles. The molar mass of copper (I) nitrate [tex](Cu(NO_3)_2)[/tex] is 187.56 g/mol, so 207.3 g of copper (I) nitrate is equal to 1.105 moles. The molar mass of potassium hydroxide (KOH) is 56.11 g/mol, so 86.7 g of potassium hydroxide is equal to 1.547 moles.

Next, we compare the moles of the reactants to the stoichiometry of the balanced equation. Since the ratio of copper (I) nitrate to potassium hydroxide is 1:2, and we have more moles of potassium hydroxide, it is the limiting reactant.

From the stoichiometry, we know that 2 moles of potassium hydroxide produce 1 mole of copper (II) hydroxide. Therefore, 1.547 moles of potassium hydroxide will produce (1.547/2) = 0.774 moles of copper (II) hydroxide.

Finally, we calculate the mass of copper (II) hydroxide using its molar mass of 97.56 g/mol. The mass is (0.774 moles) × (97.56 g/mol) = 75.4 g.

Thus, the possible yield of the solid precipitate (copper (II) hydroxide) is 75.4 g. However, it is important to note that in practice, the actual yield might be lower due to factors such as incomplete reactions or side reactions.

To learn more about precipitate refer:

https://brainly.com/question/30386923

#SPJ11


Related Questions

How many moles of F2 occupy 37 L at 15°C and 0. 53 atm?

Answers

The number of moles of F2 that occupy 37 L at 15°C and 0.53 atm is 0.805 mol.

Given that volume of gas = 37 L Pressure of gas = 0.53 atm Temperature = 15 °C = 15 + 273 = 288 KNow, let's apply the ideal gas law which is given byPV = nRT Where,P = Pressure of the gasV = Volume of the gasn = Number of moles of the gasR = Universal gas constant T = Temperature of the gas Substitute the given values in the ideal gas law and find the number of moles of F2 in 37 L at 15°C and 0.53 atm. So,PV = nRTn = PV/RTOn substituting the values, we getn = 0.53 atm × 37 L/(0.0821 L atm/K mol × 288 K)n = 0.805 molSo, the number of moles of F2 that occupy 37 L at 15°C and 0.53 atm is 0.805 mol.

learn more about moles

https://brainly.com/question/7666016

#SPJ11

Calculate the electron concentrations in Si and GaAs if the Fermi level is 0.3 eV above the valence band edge.

Answers

The electron concentrations in Si and GaAs is n(Si) ≈ 1.57 x 10¹⁹ cm⁻³ and n(GaAs) ≈ 1.15 x 10¹⁷ cm⁻³ respectively.

To calculate the electron concentrations in Si and GaAs, we need to use the relationship between the Fermi level and the electron concentration.

In intrinsic semiconductors like Si and GaAs, the Fermi level lies close to the middle of the band gap. Assuming room temperature (T = 300 K), we can use the following equation:

n = Nc × exp((Ef - Ev) / (k × T))

where:

n is the electron concentration,

Nc is the effective density of states in the conduction band,

Ef is the Fermi level,

Ev is the energy of the valence band edge,

k is the Boltzmann constant, and

T is the temperature in Kelvin.

For Si:

The energy gap (Eg) of Si is approximately 1.1 eV. Given that the Fermi level (Ef) is 0.3 eV above the valence band edge (Ev), we can calculate the electron concentration using the equation above. The effective density of states in the conduction band for Si at room temperature is approximately 2.8 x 10¹⁹cm⁻³:

n(Si) = 2.8 x 10¹⁹ x  exp((0.3 eV) / (k x  300 K))

For GaAs:

The energy gap (Eg) of GaAs is approximately 1.4 eV. Using the same Fermi level (Ef) of 0.3 eV above the valence band edge (Ev), we can calculate the electron concentration. The effective density of states in the conduction band for GaAs at room temperature is approximately 4.7 x 10¹⁷ cm⁻³:

n(GaAs) = 4.7 x 10¹⁷ x exp((0.3 eV) / (k x 300 K))

Now, let's calculate the electron concentrations in Si and GaAs using the given values:

n(Si) = 2.8 x 10¹⁹ x exp((0.3 eV) / (8.617 x 10⁻⁵ eV/K x 300 K))

n(Si) ≈ 1.57 x 10¹⁹ cm⁻³

n(GaAs) = 4.7 x 10¹⁷ x exp((0.3 eV) / (8.617 x 10⁻⁵ eV/K x 300 K))

n(GaAs) ≈ 1.15 x 10¹⁷ cm⁻³

Hence, the electron concentrations are calculated above.

Learn more about Fermi level here:

https://brainly.com/question/31872192

#SPJ 4

calculate the total pressure (in atm) in a mixture of 1.00 grams of H2 and 1.00 gram of He in a 5.00-liter container at 21 degrees C

Answers

In the case, the total pressure in the mixture is 3.47 atm.

To calculate the total pressure (in atm) in a mixture of 1.00 grams of H₂ and 1.00 gram of He in a 5.00-liter container at 21 degrees C, we use the ideal gas law. The ideal gas law is given by

PV = nRT

where

P = pressure

V = volume

T = temperaturen = number of moles of gas

R = the gas constant

The first step is to calculate the number of moles of each gas in the mixture. We can do this using the mass of each gas and their respective molar masses.

The molar mass of H2 is 2 g/molThe molar mass of He is 4 g/mol

Number of moles of H2 = mass of H2 / molar mass of H2= 1.00 g / 2 g/mol= 0.50 moles

Number of moles of He = mass of He / molar mass of He= 1.00 g / 4 g/mol= 0.25 moles

The total number of moles of gas in the mixture is 0.50 moles + 0.25 moles = 0.75 moles.

Now, we can substitute the values we have into the ideal gas law to solve for P.PV = nRTP = nRT/V

where

R = 0.0821 L atm / (mol K)

T = 21°C + 273.15 = 294.15

KP = (0.75 mol) (0.0821 L atm / (mol K)) (294.15 K) / 5.00

 L = 3.47 atm

Therefore, the total pressure in the mixture is 3.47 atm.

Learn more about total pressure at https://brainly.com/question/30235826

#SPJ11

A series of cell voltages are measured from an electrochemical cell constructed with Zn anode in 1.00 M ZnSO4 solution and Ag cathode in various standard solutions of AgNO3 from 0.0001 M to 0.1000 M. A plot of measured Ecell is plotted as function log10[Ag ] for the cell with the different concentrations of AgNO3. Predict the theoretical value of the slope of the plot

0.05916 V

0.02958 V

0.02569 V

0.01284 V

0.01690V

Predict the theoretical value of the y-intercept.

2.362 V

–1.562 V

0.455 V

–0.455 V

1.562V

Answers

The theoretical value of the slope of the plot is 0.02958 V, and the theoretical value of the y-intercept is 0.455 V.

In electrochemical cells, the measured cell potential (Ecell) can be related to the concentrations of the reactants using the Nernst equation:

Ecell = E°cell - (0.05916 V/n) * log10([Ag⁺]/[Zn₂⁺])

where E°cell is the standard cell potential, n is the number of electrons transferred in the cell reaction, [Ag⁺] is the concentration of silver ions, and [Zn₂⁺] is the concentration of zinc ions.

In this case, the anode is constructed with a zinc electrode in a 1.00 M ZnSO₄ solution, and the cathode is made of silver in various standard solutions of AgNO₃ with concentrations ranging from 0.0001 M to 0.1000 M. The plot of Ecell versus log10[Ag⁺] will give us insights into the relationship between the cell potential and the concentration of silver ions.

The slope of the plot represents the value of (0.05916 V/n), which is a constant. By observing the given choices, the closest value to 0.05916 V is 0.02958 V. Therefore, the theoretical value of the slope of the plot is 0.02958 V.

The y-intercept of the plot corresponds to the value of E°cell. Since E°cell is the standard cell potential, it remains constant regardless of the concentration of the silver ions. Among the provided choices, the closest value to E°cell is 0.455 V. Hence, the theoretical value of the y-intercept is 0.455 V.

Learn more about Electrochemical cells

brainly.com/question/30375518

#SPJ11

Which statement best describes the behavior you observed for the second order reaction (Choose all that apply). The half-life of a second-order reaction ________: Group of answer choices

Answers

The half-life of a second-order reaction decreases as the concentration of the reactant decreases: True, Increases as the concentration of the reactant decreases: False.

Increases as the concentration of the reactant increases: False, Decreases as the concentration of the reactant increases: True. Both statements 1 and 4 accurately describe the behavior observed for the half-life of a second-order reaction. The half-life decreases as the concentration of the reactant decreases and increases as the concentration of the reactant increases. Second order reactions can be defined as chemical reactions wherein the sum of the exponents in the corresponding rate law of the chemical reaction is equal to two.

The rate of such a reaction can be written either as r = k[A]2, or as r = k[A][B].

To know more about second-order reaction, click here:-

https://brainly.com/question/8139015

#SPJ11

A solution in which a solute was dissolved into diethyl ether caused the boiling point by 3.70 oC. What is the concentration of the solution in molality

Answers

The concentration of the solution in molality is 1.71M. To determine the concentration of the solution in molality (m), it is required the change in boiling point (∆Tb) and the boiling point elevation constant (Kb) of the solvent.

Molarity (M) is a measure of the concentration of a solute in a solution. It is defined as the number of moles of solute per liter of solution. The formula for molarity is:

Given information:

∆Tb = 3.70°C (change in boiling point)

Kb = boiling point elevation constant of diethyl ether (a known value)

The formula for calculating molality is:

m = (∆Tb) / Kb

m = 3.70/ 2.16 = 1.71M

Therefore, the concentration of the solution in molality is 1.71M.

Learn more about molarity, here:

https://brainly.com/question/31545539

#SPJ4

If one were to ride a hot air balloon up into the atmosphere, one would experience the concentration of gases ____________.

Answers

If one were to ride a hot air balloon up into the atmosphere, one would experience the concentration of gases decreasing.

This is because the atmosphere of Earth is composed of different layers with varying concentrations of gases. The troposphere is the layer closest to the surface of the Earth. This is where weather occurs, and it contains the highest concentration of gases. As you go higher in the atmosphere, the concentration of gases decreases because the air pressure decreases.

At the top of the troposphere, there is a boundary known as the tropopause, where the concentration of gases reaches its minimum. The next layer is the stratosphere, where the concentration of ozone gas is highest, and it helps to absorb harmful UV radiation from the sun. The concentration of gases decreases as you move into the mesosphere, and the thermosphere has the least concentration of gases. However, it is important to note that riding a hot air balloon into the atmosphere can be dangerous due to the low oxygen levels and low temperatures at high altitudes. Special equipment is needed to ensure safety.

To know more about troposphere please refer:

https://brainly.com/question/2858308

#SPJ11

The NaOH titrant in this experiment was prepared to be approximately 0.1M and then was standardized to detennine its exact concentration. What possible reasons could there be for not simply weighing the solid NaOH, dissolving to a known volume and calculating its molarity? 2. Carbon dioxide from the air dissolves in water, forming small amounts of carbonic acid, H 2

CO 3

, and causing the water to be slightly acidic. Would this tend to make your titration volume in part A of this experiment too large, too small or unchanged? Explain briefly! Would it be correct to use formula that says M acid ​
−V acia ​
=M bose ​
⋅V bue ​
at the equivalence point of a titration between H 3

PO 4

and NaOH ? Explain briefly!

Answers

There are several reasons for not simply weighing the solid NaOH to determine its molarity. Firstly, NaOH is hygroscopic, meaning it readily absorbs moisture from the air, which can affect its weight and thus the accuracy of molarity calculations.

What are the several reasons for not simply weighing the solid NaOH to determine its molarity?

There are several reasons for not simply weighing the solid NaOH and calculating its molarity:

  a. NaOH is hygroscopic, meaning it readily absorbs moisture from the air, leading to inaccuracies in weighing and molarity calculations.   b. NaOH pellets can contain impurities or water of crystallization, affecting the accuracy of molarity calculations.   c. NaOH reacts with carbon dioxide in the air, forming sodium carbonate, which can further alter the molarity.

The presence of carbon dioxide in water forming carbonic acid makes the water slightly acidic. This would tend to make the titration volume in part A of the experiment too large.

The acidic nature of the solution would require more NaOH to neutralize the excess acidity, resulting in a larger volume required for the titration.

The formula "M acid −V acid = M base ⋅V base" is not applicable to the titration between H3PO4 and NaOH at the equivalence point. This is because H3PO4 is a polyprotic acid, meaning it can donate multiple protons.

At the equivalence point, all the protons from H3PO4 are not yet neutralized, so the formula does not accurately represent the stoichiometry of the reaction.

Learn more about several reasons

brainly.com/question/20815910

#SPJ11

A 16. 4 g sample of calcium chloride is dissolved in enough water to make 750. 0 mL of solution. Calculate the molarity of calcium chloride in this solution

Answers

The molarity of calcium chloride in the solution is 0.346 M. To calculate the molarity, we need to determine the number of moles of calcium chloride present in the solution and divide it by the volume of the solution in liters.

First, we convert the mass of calcium chloride to moles using its molar mass. The molar mass of calcium chloride (CaCl2) is 110.98 g/mol. Thus, the number of moles of calcium chloride is:

[tex]\[\text{{moles of CaCl}}_2 = \frac{{16.4 \text{ g}}}{{110.98 \text{ g/mol}}} = 0.1479 \text{ mol}\][/tex]

Next, we convert the volume of the solution from milliliters to liters:

[tex]\[\text{{volume of solution}} = \frac{{750.0 \text{ mL}}}{{1000 \text{ mL/L}}} = 0.750 \text{ L}\][/tex]

Finally, we calculate the molarity by dividing the moles of calcium chloride by the volume of the solution:

[tex]\[\text{{Molarity}} = \frac{{0.1479 \text{ mol}}}{{0.750 \text{ L}}} = 0.346 \text{ M}\][/tex]

Therefore, the molarity of calcium chloride in the solution is 0.346 M.

To learn more about molarity refer:

https://brainly.com/question/14469428

#SPJ11

Radiometric dating of a rock reveals an age of 1.52 billion years. Given that the half-life of the parent isotope used is 14.0 billion years, what percentage of the parent isotope is still present in the rock

Answers

The percentage of the parent isotope still present in the rock is approximately 10.8%.

Radiometric dating relies on the decay of parent isotopes into daughter isotopes over time. The half-life of an isotope is the time it takes for half of the parent isotope to decay into the daughter isotope. In this case, the half-life of the parent isotope used for dating the rock is 14.0 billion years.

To determine the percentage of the parent isotope remaining in the rock, we can calculate the number of half-lives that have passed since the rock's formation. The age of the rock is given as 1.52 billion years, which is equivalent to 1.52/14.0 = 0.1086, or approximately 0.11 half-lives.

Each half-life halves the amount of the parent isotope, so after 0.11 half-lives, the percentage remaining can be calculated as:

Percentage remaining = (1/2)^(number of half-lives) * 100%

Plugging in the value of 0.11 for the number of half-lives, we find:

Percentage remaining = (1/2)^(0.11) * 100% ≈ 10.8%

Therefore, approximately 10.8% of the parent isotope is still present in the rock, based on the given age of 1.52 billion years and the half-life of the parent isotope of 14.0 billion years. The remaining percentage represents the portion of the parent isotope that has not yet decayed into the daughter isotope.

To read more about isotope, visit:

https://brainly.com/question/364529

#SPJ11

If all the molecules are in the gas phase, what is the change in the number of moles of gas in the equation

Answers

When all the molecules are in the gas phase, the change in the number of moles of gas in a chemical equation depends on the difference between the total moles of gas on the product side and the total moles of gas on the reactant side.

In a chemical equation, the coefficients of the reactants and products represent the relative number of moles of each substance involved in the reaction. When considering the change in the number of moles of gas in a reaction, we compare the total moles of gas on the reactant side with the total moles of gas on the product side.

If the number of moles of gas on the product side is greater than the number of moles on the reactant side, the reaction results in an increase in the number of moles of gas. Conversely, if the number of moles of gas on the product side is less than the number of moles on the reactant side, the reaction leads to a decrease in the number of moles of gas.

It's important to note that the state of matter of the substances in the equation is crucial for this analysis. In the gas phase, the number of moles of gas can change due to the formation or consumption of gaseous products or reactants.

For example, consider the reaction:

2H₂(g) + O₂(g) -> 2H₂O(g)

In this reaction, there are 4 moles of gas on the reactant side (2 moles of H₂ and 1 mole of  O₂) and 2 moles of gas on the product side (2 moles of H₂O). The reaction results in a decrease in the number of moles of gas, as the total moles of gas on the product side (2 moles) is less than the total moles of gas on the reactant side (4 moles).

know more about molecules here:

https://brainly.com/question/475709

#SPJ11

You dissolve 1.25 grams of an unknown diprotic acid in 200.0 mL of H2O. This solution is titrated to the second equivalence point using 5.00 mL of a 1.00 M NaOH solution. What is the molar mass of the unknown acid?

Answers

The molar mass of the unknown diprotic acid is 117.9 g/mol.

In a titration, a known concentration of a solution is used to determine the concentration of an unknown solution. In this case, the known solution is NaOH, which has a concentration of 1.00 M. The unknown solution is the diprotic acid, and its concentration is determined by finding the number of moles of NaOH that react with it.

The number of moles of NaOH used in the titration is equal to the volume of the NaOH solution multiplied by its concentration. In this case, the volume of the NaOH solution is 5.00 mL and its concentration is 1.00 M, so the number of moles of NaOH used is 5.00 mL * 1.00 M = 5.00 mmol.

Since the acid is diprotic, it requires 2 moles of NaOH per mole of acid. This means that the number of moles of acid in the solution is equal to half the number of moles of NaOH used. In this case, the number of moles of acid is 5.00 mmol / 2 = 2.50 mmol.

The molar mass of the acid is calculated by dividing its mass by its number of moles. In this case, the mass of the acid is 1.25 g and the number of moles is 2.50 mmol. This gives a molar mass of 1.25 g / 2.50 mmol = 117.9 g/mol.

To learn more about molar mass here brainly.com/question/31545539

#SPJ11

What is the minimum amount of 6.0M H2SO4 necessary to produce 25.0g of H2(g) according to the rxn between Aluminum and Sulfuric Acid

Answers

The minimum amount of 6.0 M H₂SO₄ necessary to produce 25.0 g of H₂(g) according to the reaction between aluminum and sulfuric acid will depend on the stoichiometry of the reaction.

To determine the minimum amount of 6.0 M H₂SO₄ needed, we need to consider the balanced equation and stoichiometry of the reaction. The balanced equation for the reaction between aluminum (Al) and sulfuric acid (H₂SO₄) is:

2 Al + 3 H₂SO₄ → Al₂(SO₄)₃ + 3 H₂

From the balanced equation, we can see that 2 moles of aluminum react with 3 moles of sulfuric acid to produce 3 moles of hydrogen gas.

First, we need to calculate the number of moles of hydrogen gas (H₂) produced from 25.0 g of H₂. We can use the molar mass of hydrogen (H₂) to convert grams to moles:

Molar mass of H₂ = 2.016 g/mol

Number of moles of H₂ = mass of H₂ / molar mass of H₂ = 25.0 g / 2.016 g/mol

Next, using the stoichiometry of the balanced equation, we can determine the number of moles of sulfuric acid (H₂SO₄) required to produce the calculated number of moles of hydrogen gas.

From the balanced equation, we know that 2 moles of aluminum react with 3 moles of sulfuric acid to produce 3 moles of hydrogen gas. Therefore, the ratio of moles of sulfuric acid to moles of hydrogen gas is 3:2.

Number of moles of H₂SO₄ = (Number of moles of H₂) x (moles of H₂SO₄ / moles of H₂) = (Number of moles of H₂) x (3/2)

Finally, to determine the minimum amount of 6.0 M H₂SO₄ required, we need to convert the moles of H₂SO₄ to volume using the molarity of the solution. The equation for converting moles to volume is:

Volume (in liters) = moles of H₂SO₄ / molarity of H₂SO₄

Substituting the calculated number of moles of H₂SO₄ into the equation will give us the minimum volume of 6.0 M H₂SO₄ needed to produce 25.0 g of H₂(g).

To know more about stoichiometry refer here:

https://brainly.com/question/28780091#

#SPJ11

Assume air is 21% oxygen on a mole percent basis and the remainder is nitrogen. Calculate the weighted average heat capacity and then use that to find the energy that would need to be removed from 10 mol of the mixture to go from 500 K to 300 K.

Answers

Approximately 8,880 J of energy would need to be removed from 10 mol of the mixture to go from 500 K to 300 K.

The weighted average heat capacity of the air mixture is approximately 29.6 J/(mol·K). Therefore, to go from 500 K to 300 K, approximately 8,880 J of energy would need to be removed from 10 mol of the mixture.

To calculate the weighted average heat capacity, we consider the mole fraction of each component and their respective heat capacities. Given that air is 21% oxygen (O₂) and 79% nitrogen (N₂) on a mole percent basis, we can calculate the mole fraction of each component. The mole fraction of oxygen is 0.21, and the mole fraction of nitrogen is 0.79.

The heat capacity of oxygen is 29.3 J/(mol·K), and the heat capacity of nitrogen is 29.1 J/(mol·K). To find the weighted average heat capacity, we multiply the mole fraction of each component by its respective heat capacity, and then sum the results:

Weighted average heat capacity = (0.21 * 29.3 J/(mol·K)) + (0.79 * 29.1 J/(mol·K))

                           = 6.153 J/(mol·K) + 22.989 J/(mol·K)

                           = 29.142 J/(mol·K) ≈ 29.6 J/(mol·K)

Now, to find the energy that needs to be removed from 10 mol of the mixture to go from 500 K to 300 K, we can use the formula:

Energy = n * ΔT * C

Where:

n is the number of moles (10 mol),

ΔT is the change in temperature (500 K - 300 K = 200 K),

C is the weighted average heat capacity (29.6 J/(mol·K)).

Plugging in these values, we have:

Energy = 10 mol * 200 K * 29.6 J/(mol·K)

      = 59,200 J ≈ 8,880 J

Therefore, approximately 8,880 J of energy would need to be removed from 10 mol of the mixture to go from 500 K to 300 K.

To know more about average heat capacity, refer here:

https://brainly.com/question/32234465#

#SPJ11

PLSSSS


A 0. 500 g sample of a compound containing only antimony and oxygen was found to contain 0. 359 g of antimony and 0. 141 g of oxygen. What is the simplest


formula for the compound?



SbO


SbO2


Sb3O4


SbO3

Answers

The simplest formula for the compound is Sb2O3 indicating that it contains two atoms of antimony and three atoms of oxygen.

To determine the simplest formula for the compound, we need to find the mole ratio between antimony (Sb) and oxygen (O).

First, let's calculate the number of moles for each element:

- Moles of antimony (Sb) = Mass of antimony (0.359 g) / molar mass of antimony (121.75 g/mol) = 0.00295 mol

- Moles of oxygen (O) = Mass of oxygen (0.141 g) / molar mass of oxygen (16.00 g/mol) = 0.00881 mol

Next, we need to find the simplest whole number ratio between the two elements.

Dividing the number of moles of each element by the smaller value (0.00295 mol), we get:

- Moles of Sb = 0.00295 mol / 0.00295 mol = 1

- Moles of O = 0.00881 mol / 0.00295 mol = 3

The mole ratio between Sb and O is 1:3. Therefore, the simplest formula for the compound is Sb2O3.

The simplest formula for the compound is Sb2O3, indicating that it contains two atoms of antimony and three atoms of oxygen.

To know more about atoms  visit :

https://brainly.in/question/13150186

#SPJ11

According to the kinetic molecular theory of gases, a gas can be compressed much more than a liquid or solid because ________.

Answers

According to the kinetic molecular theory of gases, a gas can be compressed much more than a liquid or solid because the particles of a gas are widely spaced and have high kinetic energy.

The kinetic molecular theory assumes that gas particles are in constant random motion, and they are considered to have negligible volume compared to the total volume of the gas. Therefore, when pressure is applied to a gas, the particles can be compressed into a smaller volume, as they can move closer together and occupy a smaller space. In contrast, the particles in a liquid or solid are already in proximity to each other, and they have stronger intermolecular forces that resist compression.

Hence, a gas can be compressed much more than a liquid or solid because the particles of a gas are widely spaced and have high kinetic energy.

Learn more about kinetic energy here:

https://brainly.com/question/999862

#SPJ 4

Fluoridation is the process of adding fluorine compounds to drinking water to help fight tooth decay. A concentration of 1 ppm of fluorine is sufficient for the purpose (1 ppm means one part per million, or 1 g of fluorine per 1 million g of water). The compound normally chosen for fluoridation is sodium fluoride, which is also added to some toothpastes. Calculate the quantity of sodium fluoride in kilograms needed per year for a city of 50,000 people if the daily consumption of water per person is 145.0 gallons. (Sodium fluoride is 45.0 percent fluorine by mass. 1 gallon

Answers

The quantity of sodium fluoride in kilograms needed per year for a city of 50,000 people if the daily consumption of water per person is 145.0 gallons is 12,284.128 kg/year.

To calculate the quantity of sodium fluoride in kilograms needed per year, we are given: the sodium fluoride is 45.0% fluorine by mass and the daily consumption of water per person is 145.0 gallons. Sodium fluoride is added to water for a city of 50,000 people.

A concentration of 1 ppm of fluorine is sufficient for fluoridation purposes. This means there is 1 g of fluorine in 1 million g (or 1 metric ton) of water (parts per million or ppm). Therefore, in 145.0 gallons of water, there is:

1 gallon = 3.785411784 L

145.0 gallons = 145.0 × 3.785411784 L

= 549.85476768 L

The concentration of fluorine in 1 L of water: 1 g of fluorine in 1 million g of water

The concentration of fluorine in 549.85476768 L of water = (1/1,000,000) × 549.85476768 = 0.0005498548 g of fluorine in 549.85476768 L of water

We can then calculate the amount of sodium fluoride required for a city of 50,000 people as follows:

Number of liters of water required per year: 549.85476768 L/person/day × 365 days/year × 50,000 persons

= 10,054,117,608 L/year

Mass of fluorine required per year: 0.0005498548 g of F in 1 L of water

Mass of fluorine required per year = 0.0005498548 g/L × 10,054,117,608 L = 5,527,857.8 g/year

Mass of sodium fluoride required per year: sodium fluoride is 45.0% F by mass

Mass of sodium fluoride required per year = (5,527,857.8 g/year)/(0.45)

= 12,284,128 g/year = 12.28 Mg/year = 12.28 metric tons/year= 12,284.128 kg/year

Learn more about sodium fluoride: https://brainly.com/question/2807538

#SPJ11

When aqueous solutions of Pb(NO3)2 and NaCl are mixed, PbCl2 precipitates. The balanced net ionic equation is ________.

Answers

The balanced net ionic equation for the reaction between Pb(NO₃)₂ and NaCl, resulting in the precipitation of PbCl₂, is Pb²⁺ (aq) + 2Cl⁻ (aq) → PbCl₂ (s).

When aqueous solutions of Pb(NO₃)₂ (lead(II) nitrate) and NaCl (sodium chloride) are mixed, a precipitation reaction occurs, leading to the formation of solid PbCl₂ (lead(II) chloride). The net ionic equation focuses on the species directly involved in the chemical change, excluding spectator ions that do not participate in the formation of the precipitate.

The ionic compounds dissociate in water into their respective ions:

Pb(NO₃)₂ (aq) → Pb²⁺ (aq) + 2NO₃⁻ (aq)

NaCl (aq) → Na⁺ (aq) + Cl⁻ (aq)

Upon mixing the solutions, the Pb²⁺ ions from Pb(NO₃)₂ react with the Cl⁻ ions from NaCl to form the insoluble salt PbCl₂, which precipitates out of the solution. The net ionic equation for this reaction is:

Pb²⁺ (aq) + 2Cl⁻ (aq) → PbCl₂ (s)

This net ionic equation represents the essential chemical change occurring in the reaction, emphasizing the formation of the precipitate PbCl₂. The balanced equation shows the stoichiometric relationship between the reacting ions, where one Pb²⁺ ion combines with two Cl⁻ ions to produce one molecule of PbCl₂.

To learn more about balanced net ionic equation, here

https://brainly.com/question/30801342

#SPJ4

What volume of 0.140 MNaOHMNaOH is required to reach the equivalence point in the titration of 40.0 mLmL of 0.100 MM HNO3HNO3

Answers

The volume of 0.140 M NaOH required to reach the equivalence point in the titration of 40.0 mL of 0.100 M HNO₃ is 28.6 mL.

To calculate the volume of NaOH to reach the equivalence point in the titration of HNO₃, we must write the balanced chemical equation is:

HNO₃(aq) + NaOH(aq) → NaNO₃(aq) + H₂O(l)

In the reaction between HNO₃ and NaOH, 1 mole of NaOH reacts with 1 mole of HNO₃. So, the number of moles of NaOH required to neutralize 1 mole of HNO₃ is 1.

According to the question, the volume of HNO₃ is 40.0 mL and the concentration of HNO₃ is 0.100 MM. To calculate the number of moles of HNO₃:

molarity = number of moles / volume (in L)

number of moles = molarity × volume (in L)

number of moles of HNO₃ = 0.100 M × (40.0 mL / 1000 mL/L)

= 0.00400 moles

Now, as 1 mole of NaOH reacts with 1 mole of HNO3, so 0.00400 moles of NaOH are required to react with HNO₃.

According to the question, the concentration of NaOH is 0.140 M. So, to calculate the volume of NaOH required:

moles of NaOH = molarity × volume (in L)

volume (in L) = moles of NaOH / molarity

volume of NaOH = 0.00400 moles / 0.140 M

= 0.0286 L = 28.6 mL

Learn more about volume: https://brainly.com/question/29097593

#SPJ11

why do glass based ceramic crowns have a more life like appearance than porcelain bonded to metal crowns

Answers

Glass-based ceramic crowns tend to have a more lifelike appearance than porcelain bonded to metal (PFM) crowns due to a few key factors such as allergic reactions, metal-free PFM, aesthetics, etc.

Translucency: Compared to the opaque metal core used in PFM crowns, glass-based ceramic materials, such as lithium disilicate or zirconia-reinforced lithium silicate, offer increased translucency.

Aesthetics: Glass-based ceramics may be more effectively matched in terms of color, tone, and texture to the neighboring natural teeth.

Metal-free: Unlike PFM crowns, glass-based ceramic crowns lack a metal underpinning.

Allergic reactions: PFM crowns include metal alloys, which some people may be sensitive to.

To know more about (PFM):

https://brainly.com/question/31830461

#SPJ4

When 0.103 g of Zn( s ) is combined with enough HCl to make 50.0 mL of solution in a coffee-cup calorimeter, all of the zinc reacts, raising the temperature of the solution from 22.5 C to 23.7 C. Find Hrxn for this reaction as written. (Use 1.0 g/mL for the density of the solution and 4.18 J/g

Answers

The answer is -0.251 kJ as Hrxn for this reaction as written.

The reaction between Zn( s ) and HCl can be described as follows:Zn(s) + 2HCl(aq) ⟶ ZnCl2(aq) + H2(g)From the balanced equation above, one mole of zinc produces one mole of hydrogen gas. Hence, 0.103 g of zinc produced:0.103g Zn(1mol/65.38g) = 1.579 × 10-3 moles of Zn.Moles of H2 = 1.579 × 10-3 moles by stoichiometry.Mass of solution = 50.0 g/1.0 mL × 1.0 g/mL = 50.0 g.Let's calculate the change in temperature of the solution:ΔT = Tfinal – Tinitial = 23.7 °C – 22.5 °C = 1.2 °C.From the above information, we can calculate the heat of reaction as follows:qrxn = -(Cp × m × ΔT)where Cp = heat capacity of the solution, m = mass of solution, and ΔT = change in temperature of the solution.

The heat capacity of the solution, Cp = 4.18 J/g °C.Mass of solution, m = 50.0 g.So, qrxn = -(4.18 J/g °C × 50.0 g × 1.2 °C) = -251 J.Hence, the value of Hrxn is -251 J or -0.251 kJ. Therefore, the answer is -0.251 kJ as Hrxn for this reaction as written.

Learn more about Hydrogen here,What are the uses of hydrogen?

https://brainly.com/question/24433860

#SPJ11

The expression of K eq for the following reaction will not include ________. A(g) B(g) C(l) D(g)

Answers

The expression of K(eq) for the given reaction will not include C(l).

Hence, the correct option is C.

The expression of K(eq) for the given reaction will not include the concentration of the liquid phase C(l).

In the expression of the equilibrium constant, K(eq), only the concentrations of the reactant and product gases are included. The concentrations of pure solids or pure liquids are not included because they are considered to have a constant concentration and do not affect the equilibrium expression.

Therefore, in the given reaction, the expression of K(eq) will include the concentrations of A(g), B(g), and D(g) but not the concentration of C(l).

To know more about reaction here

https://brainly.com/question/13745683

#SPJ4

-- The given question is incomplete, the complete question is

"The expression of K(eq) for the following reaction will not include ________.

A(g) + B(g) = C(l) + D(g)

1.A(g) 2. B(g) 3. C(l) 4. D(g)" --

One of the radioactive isotopes used in medical treatment or analysis is phosphorus-32. The half-life of phosphorus-32 is 14 days. How many days is/are required for the activity of a sample of phosphorus-32 to fall to 12.5 percent of its original value

Answers

The days required for the activity of a sample of phosphorus-32 to fall to 12.5 percent of its original value is 56 days.

Phosphorus-32 has a half-life of 14 days, which means that it takes 14 days for half of the initial amount of phosphorus-32 to decay.

On taking 100 units of phosphorus-32, after the first half-life of 14 days, the activity will be reduced to 50 units . After another 14 days the activity will be reduced to 25 units in the second half-life period. after another half-life period the activity will be reduced to 12.5%. The number of days required for decay to 12.5% is 4 half-life periods.

[tex]4*14=56[/tex] days

Therefore, the number of days required for the fall of activity of phosphorus-32 to 12.5 units is 56 days.

To know more about half-life period, visit:

https://brainly.com/question/31816111

#SPJ12




If 18 grams of Ca combines with 22 grams of S to form a compound with a


mass of 40 grams, what will be the percent composition of S in the


compound?

Answers

The per cent composition of S in the compound can be found by the following formula:% composition of S in the compound = (mass of S in the compound / total mass of the compound) × 100.

We are given the mass of the compound, which is 40 grams, but we need to find the mass of S in the compound. To find the mass of S in the compound, we can subtract the mass of Ca from the total mass of the compound: Mass of S in the compound = Total mass of the compound - Mass of Ca in the compound. Mass of S in the compound = 40 g - 18 g, Mass of S in the compound = 22 g.

Now, we can substitute the values we have into the per cent composition formula:% composition of S in the compound = (22 g / 40 g) × 100% composition of S in the compound = 55%.

Therefore, the per cent composition of S in the compound is 55%.

Learn more about compound here ;

https://brainly.com/question/14117795

#SPJ11

What are the small chemicals, usually inorganic ions, that temporarily attach to the surface of an enzyme and promote a chemical reaction

Answers

The small chemicals that temporarily attach to the surface of an enzyme and promote a chemical reaction are called cofactors.

Cofactors are essential components in enzyme catalysis, playing a crucial role in promoting chemical reactions. They can be classified into two main types: inorganic cofactors and organic cofactors (coenzymes).

Inorganic cofactors: Inorganic cofactors are usually metal ions that temporarily attach to the surface of the enzyme and participate in the catalytic process. Some common examples include:

Metal ions like magnesium, zinc, iron, copper, and manganese can act as cofactors.These metal ions can bind to specific sites on the enzyme, often at the active site or other binding sites, and assist in substrate binding, catalysis, or stabilization of reaction intermediates.The coordination chemistry of these metal ions allows them to interact with the enzyme and substrate, facilitating the reaction by providing additional charge stabilization, coordination geometry, or redox properties.

Organic cofactors (Coenzymes): Coenzymes are small organic molecules that are derived from vitamins or other precursors. They are usually involved in enzyme catalysis by carrying specific functional groups or participating in electron transfer reactions. Some examples of organic cofactors include:

Nicotinamide adenine dinucleotide and flavin adenine dinucleotide. They act as electron carriers and participate in redox reactions.Coenzyme A (CoA) is derived from pantothenic acid and plays a central role in metabolism by carrying and transferring acyl groups.Tetrahydrofolate (THF) is derived from folic acid and serves as a carrier of one-carbon units in various metabolic reactions.Adenosine triphosphate (ATP) is a nucleotide coenzyme involved in energy transfer and as a source of phosphate groups in phosphorylation reactions.These organic cofactors bind to the enzyme at specific sites, either directly participating in the reaction or assisting in substrate binding and stabilization. They provide functional groups or transfer chemical species to facilitate the reaction process.

In summary, cofactors, including inorganic ions and organic coenzymes, play essential roles in enzyme catalysis. They bind to enzymes and provide additional chemical functionality, aiding in substrate binding, stabilization of reaction intermediates, electron transfer, or other necessary steps in the catalytic process. Without these cofactors, many enzymes would not be able to carry out their catalytic functions effectively.

To know more about cofactors follow the link:

https://brainly.com/question/30617241

#SPJ4

How many grams of lead is in a 750ml solution with 2ppm of lead? (Density of the soluton is 1.2g/ml)

Answers

1.8 grams of lead is in a 750mL solution with 2ppm of lead, we calculated the mass of lead in a 750 mL solution with a concentration of 2 ppm of lead, given that the density of the solution is 1.2 g/mL..

The concentration of lead in the solution is given in parts per million (ppm), and the volume and density of the solution are also provided.

Firstly, we need to convert the concentration of lead from ppm to grams per milliliter (g/mL), since the density of the solution is given in g/mL. One part per million is equivalent to one milligram per liter (mg/L), or one microgram per milliliter (μg/mL). Since the molecular weight of lead is 207.2 g/mol, we can convert ppm to g/mL as follows:

2 ppm = 2 mg/L

= 2 μg/mL

= 2 x 10^-6 g/mL

Next, we can calculate the total mass of the solution:

Mass = Volume x Density

Mass = 750 mL x 1.2 g/mL

= 900 g

Finally, we can calculate the mass of lead in the solution using the concentration of lead in g/mL:

Mass of lead = Concentration x Volume x Density

Mass of lead = (2 x 10^-6 g/mL) x 750 mL x 1.2 g/mL

Mass of lead = 1.8 g

Therefore, there are 1.8 grams of lead in a 750mL solution with 2ppm of lead.

We first converted the concentration from ppm to g/mL, and then calculated the total mass of the solution using the volume and density. Finally, we calculated the mass of lead in the solution using the concentration, volume, and density. The result shows that the solution contains 1.8 grams of lead.

To know more about lead, visit:

https://brainly.com/question/29801245

#SPJ11

The half-reaction at an electrode is Mg2 (molten) 2e Mg(s) Calculate the number of grams of magnesium that can be produced by supplying 1.00 F to the electrode.

Answers

Total, 0.252 milligrams (mg) of magnesium can be produced by supplying 1.00 F of electricity to the electrode.

To calculate the number of grams of magnesium (Mg) that can be produced by supplying 1.00 F (Faraday) to the electrode, we need to use the Faraday's law of electrolysis and the molar mass of magnesium.

The Faraday's law of electrolysis states that the amount of substance produced or consumed during an electrolysis process is directly proportional to the quantity of electricity passed through the system. The relationship is given by:

Mass of substance (grams) = (Electric charge in Coulombs) / (Faraday's constant) × (Molar mass of substance)

The Faraday's constant is the charge of one mole of electrons, which is approximately 96,485 C/mol.

Given;

Electric charge = 1.00 F

Molar mass of magnesium (Mg)=24.31 g/mol

Let's calculate the number of grams of magnesium produced:

Number of moles of Mg = (Electric charge in Coulombs) / (Faraday's constant)

= 1.00 F / 96,485 C/mol

≈ 1.036 x 10⁻⁵ mol

Mass of Mg = Number of moles of Mg × Molar mass of Mg

= 1.036 x 10⁻⁵ mol × 24.31 g/mol

≈ 2.52 x 10⁻⁴ grams

Therefore, approximately 0.252 milligrams (mg) of magnesium can be produced by supplying 1.00 F of electricity to the electrode.

To know more about magnesium here

https://brainly.com/question/22370698

#SPJ4

The reaction of ethyl bromide with sodium hydroxide:


CH3CH2Br(aq)+NaOH(aq)⇌CH3CH2OH(aq)+NaBr(aq)


is first order in CH3CH2Br and first order in NaOH. If the concentration of CH3CH2Br was increased by half and the concentration of NaOH was quadrupled, by what factor would the reaction rate increase?

Answers

The reaction rate would increase by a factor of 6 when the concentration of [tex]CH_{3}CH_{2} Br[/tex] is increased by half and the concentration of NaOH is quadrupled.

The rate of a chemical reaction is determined by its rate equation, which expresses the relationship between the reaction rate and the reactants' concentrations. In this case, the rate equation can be written as:

Rate = k[[tex]CH_{3}CH_{2} Br[/tex]][NaOH]

Given that the reaction is first order in both [tex]CH_{3}CH_{2} Br[/tex] and NaOH, the rate equation can be simplified as:

Rate = k'[[tex]CH_{3}CH_{2} Br[/tex]][NaOH]

Where k' is the rate constant.

Now, let's consider the effect of changing the concentrations of the reactants. If the concentration of [tex]CH_{3}CH_{2} Br[/tex] is increased by half, it means the new concentration is 1.5 times the original concentration. Similarly, if the concentration of NaOH is quadrupled, it means the new concentration is 4 times the original concentration.

Substituting these values into the rate equation:

New Rate = k'(1.5[[tex]CH_{3}CH_{2} Br[/tex]])(4[NaOH])

Comparing this to the original rate:

Original Rate = k'[[tex]CH_{3}CH_{2} Br[/tex]][NaOH]

The factor by which the rate increases can be found by dividing the new rate by the original rate:

Rate increase factor = (k'(1.5[[tex]CH_{3}CH_{2} Br[/tex]])(4[NaOH])) / (k'[[tex]CH_{3}CH_{2} Br[/tex]][NaOH])

The rate constant k' cancels out, and [NaOH] also cancels out:

Rate increase factor = (1.5)(4) = 6

Therefore, the reaction rate would increase by a factor of 6 when the concentration of [tex]CH_{3}CH_{2} Br[/tex] is increased by half and the concentration of NaOH is quadrupled.

Learn more about reaction rate:

https://brainly.com/question/12904152

#SPJ11

A buffer that contains 1. 05 m base, b, and 0. 700 m of its conjugate acid, bh+ , has a ph of ph = 9. 300. What is the ph after 0. 0045 mol of hcl is added to 0. 450 l of this solution?

Answers

The pH of the buffer solution is 9.300. After adding 0.0045 mol of HCl to 0.450 L of the solution, the pH will decrease.

To determine the new pH of the solution after adding HCl, we need to consider the reaction that occurs between HCl and the buffer components, which are the base (B) and its conjugate acid (BH+):

[tex]\[\text{B} + \text{HCl} \rightarrow \text{BH+} + \text{Cl-}\][/tex]

Initially, the buffer solution has a pH of 9.300, indicating that it is basic. This means the concentration of BH+ is greater than that of B. Upon adding HCl, the H+ ions from HCl react with BH+ to form more B. As a result, the concentration of BH+ decreases, and the pH of the solution decreases.

To calculate the new pH, we need to determine the final concentrations of B and BH+. We know that the initial volume of the solution is 0.450 L, and the initial moles of BH+ is given as 0.700 m. After adding 0.0045 mol of HCl, the final moles of BH+ will be 0.700 m - 0.0045 mol. The final moles of B can be calculated as 0.0045 mol (since one mole of HCl reacts with one mole of BH+).

Next, we convert the moles of B and BH+ to concentrations by dividing by the final volume of the solution, which remains the same at 0.450 L. With the concentrations of B and BH+, we can calculate the new pH using the Henderson-Hasselbalch equation:

[tex]\[\text{pH} = \text{pKa} + \log\left(\frac{[\text{B}]}{[\text{BH+}]}\right)\][/tex]

where pKa is the negative logarithm of the acid dissociation constant of BH+.

By substituting the values into the equation, we can determine the new pH of the solution after adding HCl.

To learn more about buffer solution refer:

https://brainly.com/question/8676275

#SPJ11

The unique properties of an element will definitely change into those resembling another element if we alter the number of

Answers

The unique properties of an element will definitely change into those resembling another element if we alter the number of protons in its nucleus.

The number of protons in an element's nucleus is what defines it as a unique and distinct chemical species. It is called the atomic number and determines the element's identity. The unique properties of an element, such as its chemical reactivity, physical state, and chemical behavior, are determined by its atomic structure.

If we alter the number of protons in an element's nucleus, we change its atomic number and thus its identity. The element will turn into another element with different physical and chemical properties, which may or may not resemble its former characteristics.

For example, if we add two protons to an atom of carbon (which has six protons), turning it into an atom of oxygen (which has eight protons), we change its unique properties, such as carbon's ability to form four covalent bonds and its role in organic chemistry. Oxygen, on the other hand, is a reactive gas that supports combustion and is a vital component of many biomolecules.

In summary, the number of protons in an element's nucleus is essential in determining its unique properties. Altering this number would modify its atomic identity, leading to different physical and chemical properties, which may or may not resemble its former characteristics.

To know more about protons, visit:

https://brainly.com/question/1481324

#SPJ11

Other Questions
You are Julia, a new accounts receivable clerk for a paper and office supply store. Toward the end of the month, Carol Reed, a very personable sales associate, tells you that the previous A/R clerk always recorded a sales invoice when she got a verbal agreement from a customer to buy paper or office supplies. She has a verbal order from her favorite customer for $10,000 of paper and wants you to create a sales invoice today. You know that in order to create a sales invoice you need a purchase order from the customer. You also know that Ms. Reed receives a bonus for any month when her sales exceed $20,000. Would you agree to her request, and why Irene and William are having their first child. Irene knows her blood type is A, but William does not know his blood type. However, William knows that his mother and father were B. Their first child is a boy named Gregory. Gregory has type o blood. Of course, Irene and William do not understand how this happened. You could explain this to them using which of the following choices? a. Irene's genotype is AA, and William's genotype is 00; thus, Gregory expresses the phenotype of O.b. Gregory's blood type will need to be checked after his first month of life if the parents want to know his blood type. It takes about a month for the blood type to develop in a newborn child. c. Because his parents were both type B, William could not be the father of Gregory. d. Irene's genotype is AO, and William's genotype is BO; thus, Gregory expresses the phenotype of O e. Since Irene is type A, there had to be a mix-up in the lab report. Gregory should have been type A. Why did some economists and policymakers believe that the Fed's policy actions during the 2020 recession might have increased moral hazard problems in the financial system? A. By helping only the most established banks during the 2020 recession, the Fed incentivized them to make fewer loans in the future in order to secure aid during recessions B. By increasing the interest rate during the 2020 recession, the Fed encouraged people to care more about saving money than improving the economy C. The Fed once again provided relief to companies and banks who acted in a risky manner and that may encourage risky behavior by other firms who believe they will be bailed out during recessions D. By decreasing the money supply during the 2020 recession, the Fed signaled to consumers that saving is less important than spending Although antacids such as TUMS (calcium carbonate) are not dangerous, in very high concentrations, TUMS can alter the pH of your stomach (which can cause harm!). Write the chemical formula for calcium carbonate: ___________ (a) If TUMs (calcium carbonate) is an antacid, is calcium carbonate an acid or a base? ______(b) The lethal dose of calcium carbonate is 0. 00645 M calcium carbonate. If I have 1. 25 L of water in my stomach, how many moles of carbonate ions do I have in my stomach?(c) I set up a titration with 0. 045 M HCl to titrate the 1. 25 L of 0. 00645 M calcium carbonate. How many mL of the HCl solution will I need to use to titrate the calcium carbonate? Fill in the blanks please ASK YOUR TEACHER PRACTICE ANOTHER A balloon is at a height of 40 meters, and is rising at the constant rate of 5 m/sec. A bicyclist passes beneath it, traveling in a straight line at the constant speed of 10 m/sec. How fast is the distance between the bicyclist and the balloon increasing 2 seconds later What changes in society helped allow women like those pictured here to begin challenging social norms during the late nineteenth century Hey can anyone pls write a outline for african american womans they can be from these fields etc and it should be from (introduction, opening credits and body ofdocumentary to the end credits). They have to be us citizen!ScienceHistoryPolitics/Government/Civil RightsMathematicsReligionetc A space station is built in the form of a large circular structure with a radius of 100 m. the rooms of the station are all built such that the outer surface is the floor of each room. how fast would the space station have to spin (in m/sec) for the floor to exert a force on a 75 kg station crew member equivalent to the normal force exerted by a floor on the surface of earth? what trend exists between the molarmass and boiling point for compounds containing hydrogen bonded to a group 14 element Which labeling component refers to a specific amount of food that contains the quantity of nutrients described on the Nutrition Facts label QUESTION 6 Infant/toddler teachers determine how an infant or toddler perceives and processes information by using: What is the raitio for 180 students and 35 chaperones A 4.0 m diameter playground merry-go-round, with a moment of inertia of , is freely rotating with an angular velocity of 2.0 rad/s. Ryan, whose mass is 80 kg, runs underground around the outer edge of the merry-go-round in the opposite direction to its rotation still moving, he jumps directly onto the rim of the merry-go-round, bring it and himself to a halt. How fast was Ryan running when he jumped on Mr Bogasu the English teacher of the grade 12 learners planned to resign at the end of the year and become a taxi owner as he has lost interest in his work. The following is a sample of income and expenses of one month from one taxi owner mentoring him. income :R15900expenses:Taxi R350Taxi R450insurance R362maintenance cost:car R80fuel R9500repairs R600Total of income:R15900Total of expenses:R113421. What are variable cost ?2. List three variable cost. 3. Did mentor make profit? show all calculations. 4. Determine the mentor 's profit margin. Round off to two decimal numbers. 5. How can the mentor increase his profit? When material presented first produces a greater effect than material presented later, this is known as the ________. When the material presented last produces a greater effect than material presented earlier, this is known as the ________. Find the perimeter of the composite figure, made up of two semicircles and a rectangle. Use 22 as an approximation for 3. 14 In the United States, less than _____ of children under age 11 study a language other than English in school. A car is on a Ferris wheel with a radius of 20 ft. To the nearest foot, how far does the car travel over an angle of radians? Mr. Peralta has a student in his class who engages in severe tantrum behavior. He is working with the special education teacher and the behavioral support specialist on some strategies to reduce the severity of the tantrums. Each time a tantrum occurs, he records the length of time that it lasts to determine any change in the behavior. This type of sampling is called:_________.