Answer:
a) 34 g
b) 18.33 moldm^-3
Explanation:
a) The equation of the reaction is;
2NaNO3----------> 2NaNO2 + O2
Let us recall that 1 mole of a gas occupies 22.4 dm^3. Since 1 mole of O2 is produced in the reaction, we can write;
2 moles of NaNO3 yields 22.4 dm^3 of O2
x moles of O2 yields 4.5 dm^3 of O2
x = 2 * 4.5/22.4
x = 0.4 moles of NaNO3
But number of moles = mass/molar mass
molar mass of NaNO3 = 85 g/mol
Mass of NaNO3 = 0.4 moles * 85 g/mol
Mass of NaNO3 = 34 g
b)
Number of moles in 200g of HCl = mass/molar mass
molar mass of HCl = 36.5 g/mol
Number of moles = 200g/36.5 = 5.5 moles
From;
Number of moles = concentration * volume in dm^3
concentration = Number of moles/ volume in dm^3
But volume = 300 cm^3 or 0.3 dm^3
concentration = 5.5/0.3 = 18.33 moldm^-3
how many moles of tin are there in 50 g of tin (II) oxide
Answer:
Moles of tin = 0.37 mol
Explanation:
Given data:
Mass of tin oxide = 50 g
Moles of tin = ?
Solution:
Number of moles of SnO:
Number of moles = mass/molar mass
Number of moles = 50 g/ 134.71 g/mol
Number of moles = 0.37 mol
We can see there is only one mole of Sn is present in one mole of tin oxide.
Thus in 0.37 mol of tin oxide,
0.37 mol × 1 = 0.37 mol of tin
This substance consists of two or more different elements chemically combined
How many grams of carbon are required to produce 0.460 moles of SiC?
SiO2 + C → SiC + CO
Answer:
Sick Core corona +iep =Qurintine
Which elements did the Curies discover?
A. thorium and polonium
B. radium and uranium
C. radium and polonium
D. uranium and curium
Answer:
B on edge
Explanation:
Curies discovered two new radioactive elements radium and polonium.
What becomes the first detail observed through the Curies?They first determined polonium, named for Marie's place of origin Poland, in July 1898. whilst Marie Curie become joined via her physicist husband Pierre Curie to have a look at uraninite, then known as pitchblende, a uranium-rich mineral, and ore.
What 3 matters did Marie Curie find out?Indefatigable notwithstanding a profession of bodily demanding and in the end fatal work, she located polonium and radium, championed the use of radiation in medication, and basically changed our information about radioactivity. Curie changed into born Marya Skłodowska in 1867 in Warsaw.
Learn more about radioactive elements here: https://brainly.com/question/2902625
#SPJ2
Because of this, railroads use the reaction to provide molten steel to weld steel rails together when laying track. When 23.00g of iron(III) oxide reacts with aluminum metal, how many moles of molten iron (Fe) are formed
Answer:
0.288 mole of Fe.
Explanation:
We'll begin by calculating the number of mole present in 23.00g of iron(III) oxide (Fe2O3). This can be obtained as follow:
Mass of Fe2O3 = 23 g
Molar mass of Fe2O3 = (56×2) + (16×3)
= 112 + 48
= 160 g/mol
Mole of Fe2O3 =?
Mole = mass /Molar mass
Mole of Fe2O3 = 23 / 160
Mole of Fe2O3 = 0.144 mole
Next, we shall write the balanced equation for the reaction. This is given below:
2Al + Fe2O3 —> Al2O3 + 2Fe
From the balanced equation above,
1 mole of Fe2O3 reacted to produce 2 moles of Fe.
Finally, we shall determine the number of mole of Fe produced by the reaction of 23 g (i.e 0.144 mole) of Fe2O3. This can be obtained as illustrated below:
From the balanced equation above,
1 mole of Fe2O3 reacted to produce 2 moles of Fe.
Therefore, 0.144 mole of Fe2O3 will react to produce = 0.144 × 2 = 0.288 mole of Fe.
Thus, 0.288 mole of Fe is obtained from the reaction.
Hey please answer this thanks.
Explanation:
Percentage composition of oxygen = (80/134) * 100% = 59.7%.
a compound contains 64g of O and 8g of H. what is the empirical formula for this compound
Explanation:
Moles of Oxygen = 64/16 = 4
Moles of Hydrogen = 8/1 = 8
Hence the empirical formula is H2O.
What do electric conducts and thermal conducts have in comman?
Usually electrical conductors have loosely bound electrons. Materials that conduct heat are thermal conductors
Haley is trying to pull an object upward. The below forces are acting on the object.
Fp= 5500 N
Fg= 6000 N
Which represents the net force?
← 500 N
→ 500 N
↑ 500 N
↓ 500 N
Explanation:
it's answer is last
hope it helps you
↓ 500 N represents the net force as the force is acting in downward direction.
What is force?
Force is defined as a cause which is capable of changing the motion of an object. It can cause an object which has mass to change it's velocity. It is also simply a push or a pull . It has both magnitude as well as direction.Hence, it is a vector quantity.
It has SI units of Newton and is represented by'F'.Newton's second law states that force which acts on an object is equal to momentum which changes with time. If mass of object is constant, acceleration is directly proportional to net force acting on an object.
The concepts which related to force are thrust and torque .Thrust increases the velocity of an object and torque produces change in rotational speed of an object.
Learn more about force,here:
https://brainly.com/question/30507236
#SPJ7
Why do atoms become larger as you move down a group?
O The numbers of energy levels increase.
O Electron shielding increases.
O The decrease in ionization energy.
O The mass of the atom increases.
Explanation:
option C is the correct answer of this question
Ms. Terries was given a beautiful deep red gem. She knew she might be holding a ruby. Or, she might be holding a stone worth more than rubies, a stone rared than diamonds – a red beryl. Ms. Terries needed to be careful in her calculations. Red Beryl is a mixture of minerals and its density can be anywhere from 2.63g/cm3 to 2.92 g/cm3 Rubies can also vary in density from 3.9 g/cm3 to 4.1 g/cm3. Ms. Terries weighed the stone. It weighed 4.35 g. When put into a graduated cylinder of water, the water level rose 1.5 mL. Determine the density of the gem. Was it ruby or red beryl?
Answer:
red beryl
Explanation:
Red Beryls = Density range is 2.63g/cm3 to 2.92 g/cm3
Rubies = Density Range is 3.9 g/cm3 to 4.1 g/cm3
Mass of stone = 4.35 g
Volume of solid = change in water level = 1.5 mL = 1 cm3
Relationship between mass, volume and density is given by;
Density = Mass / Volume
Density = 4.35 / 1.5 = 2.9 g/cm3
The density of the stone falls in the red beryls range hence it is a red beryl.
why is ketchup a physical change
Answer:
Ketchup is not a change, it is a sauce.
Explanation:
Answer:
There is no change in the tomatos structure its "state of matter" you could say is changed, but the actual chemical compoud is the same.
A 100 gram sample of naturally occurring boron contains 19.78 % of B-10 and 80.22 % of B-11. Which numerical setup can be used to determine the atomic mass of naturally occurring B
Answer:
The required numerical set up is;
RAM = (19.78% * 10) + (80.22% * 11)
Explanation:
The relative atomic mass is the sum of the products of the mass of each isotope and its relative abundance.
Hence the relative atomic mass of Boron is obtained form;
RAM = (19.78% * 10) + (80.22% * 11)
RAM = (1.978) + (8.8242)
RAM =10.8022
What is the standard unit of measurement for length ?
A Mile
B Centimeter
C Meter
D Yard
Answer:
meter
have a nice holiday
Answer:
The Meter
Explanation:
In the metric system, the meter is the standard measurement of length.
Hope it helped!
HELP!!!
find the balanced equation
Answer:
3Fe²⁺ + Cl₂ ⇒ 2Fe³⁺ + 2Cl⁻
Explanation:
manipulate the problem to match charges and have the same amount of reactants and products on both sides.
In the ground state, all of the atoms of Period 3 elements have the same
Answer:
Shell number
Explanation:
Which sentence is a scientific statement?
A.
There is a substance around us that cannot be detected.
B.
Kids should go to school for 12 years.
C.
Experimentation is the best way to obtain knowledge.
D.
Unicorns once existed on Earth.
E.
There are no living things on the Moon.
B. Kids should go to school for 12 years.
What is a scientific statement?Scientific statements are those statements that must be falsifiable which means that able to be proven false while on the other hand, tautology is a statement that is true. The sun revolves around the earth” is an example of scientific statement because this statement can be falsifiable in the light of evidences and researches. Hypothesis is a statement that may be true or false. We can verify it by doing experiments.
So we can conclude that option B is the sentence that represents a scientific statement.
Learn more about scientific here: https://brainly.com/question/17216882
#SPJ1
What does supersaturated mean?
A.The solvent is holding as much solute as it can
B.The solvent can hold more solute
C.There is more solute than the solvent can hold
Explanation:
There is more solute than the solvent can hold (C).
What will the subscript for NH4 be?
Answer:
2
Explanation:
The subscript on Ammoniumwhich is (NH4) is 2.
Hope this helped!
eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
Answer is:
either A, or D
Explanation:
Ralph wanted to breed a pea plant that produced only purple flowers. He continued to breed purple-flowers producing pea plants together over six generations. The results of Ralph's artificial selection are shown above. What did artificial selection do the population of pea plants?
Answer:
B
Explanation:
Number of purple flowers
Number of white flowers
1
705
224
2
792
189
3
834
102
4
889
84
5
938
21
6
952
0
Ralph wanted to breed a pea plant that produced only purple flowers. He continued to breed purple-flower producing pea plants together over six generations. The results of Ralph's selective breeding are shown above. What did the selective breeding do to the population of pea plants?
A. increased its genetic diversity
B. decreased its genetic diversity
C. caused a new species of pea plant to form
D. caused a pea plant to exhibit a new characteristic
The correct answer would be that selective breeding decreased the genetic diversity of the population of the pea plants.
The genetic diversity of a population can be viewed as the number of genes in the gene pool of the population.
With each successive generation, more purple-flowered and less white-flowered pea plants were being produced until the 6th generation when only purple-flowered pea plants were produced. The ratio of the purple color gene to that of white color kept increasing until there was no longer a white color gene in the population. Hence, the genetic diversity of the population was decreased by the selective breeding.
The correct option is B
The structures of three hydrocarbons are given below : a. They have same physical properties. B.They have same structural formula. c.They have same general formula. D.They are isomers of each other.
Answer:
The correct answer is option C "They have same general formula"
Explanation:
Hydrocarbons are any of a class of natural substance intensifies made distinctly out of the components carbon (C) and hydrogen (H). The carbon particles consolidate to shape the structure of the compound, and the hydrogen molecules append to them in various arrangements.
Hydrocarbons are the chief constituents of oil and gaseous petrol. They fill in as powers and ointments just as crude materials for the creation of plastics, strands, rubbers, solvents, explosives, and modern chemical substances.
All of the compounds given are alkanes and they have the same general formula which is represented by CnH2n+2, where ‘n’ is the number of carbon atoms.
Which two statements are true about redox reactions?
A. They include both oxidation and reduction reactions,
B. Electrons are transferred.
C. They are double-replacement reactions.
D. They are acid-base reactions,
Answer:
A. They include both oxidation and reduction reactions AND B. Electrons are transferred.
Explanation:
a p e x
The statements that are true about redox reaction are:
A. They include both oxidation and reduction reactions,
B. Electrons are transferred.
What is a redox reaction?The Redox reaction is the one in which oxidation and reduction take place simultaneously. In this process transfer of electrons takes place which further leads to oxidation or reduction.
Thus, options A and B are correct.
Find more information about Redox reaction here:
brainly.com/question/21851295
How many grams of water would require 2250 joules of heat to raise it’s temperature from 34.0 C to 100.0 C ?
Answer:
8.117grams
Explanation:
its obtained from Q=MCT where
Q-HEAT REQUIRED
C-SPECIFIC HEAT CAPACITY OF WATER
M-MASS OF WATER
T-TEMPERATURE CHANGE(100C-34C)
True or false: an amplifier can adjust the amplitude
Answer:
ᴛʀᴜᴇ.................
point Deshawn ran the 400 m race(in a straight line) in 2 minutes. What is his distance and displacement ? Explain your answer below in complete sentences.
His distance and displacement are the same, which was 400 m
Further explanationGiven
Distance = 400 m
time = 2 min
Required
Distance and displacement
Solution
Distance is a scalar quantity that indicates the length of the trajectory that is traveled by an object within a certain interval. Distance has no direction, only has magnitude
Can be simplified distance = totals traveled
Displacement is a vector quantity that shows changes in the position of objects in a certain interval of time. Displacement has magnitude and direction
Can be simplified displacement = distanced traveled from starting point to ending point
From the definition above shows that the displacement and the distance that he traveled have the same value (magnitude), which is equal to 400 m
The value of the two will be different if he starts and finishes at the same point, then the displacement value is zero while the distance he has traveled is still 0
Based only on the distance between the valence electron and the nucleus, which atom has a stronger attraction between its nucleus and its valence electrons? How do you know? Please explain in at least 2 sentences.
lithium and sodium
Answer:
Lithium
Explanation:
Although sodium may seem like a viable answer because it has more protons (and thus a greater attractive force) in its nucleus, we need to take into account what "valence electrons" means. Valence electrons are, simply, electrons that are on the outermost electron shell of an atom. Sodium has an additional shell of electrons compared to lithium that are far away from the nucleus. Thus, lithium, which has valence electrons closer to its nucleus, would have a stronger attraction between its nucleus and its valence electrons.
What is the name of the particle made up of 2 protons and 2 neutrons?
Answer: It’s called a alpha particle
Explanation:
Is silver a metal or non-metal
Answer:
metal
Explanation:
All matter has both physical and chemical properties.
True or False
Answer:
F
Explanation:
