Answer:
13.7 moles
Explanation:
Given data:
Number of moles calcium carbonate = ?
Formula units calcium carbonate= 8.23 × 10²⁴
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 8.23 × 10²⁴ formula units:
one mole = 6.022 × 10²³ formula units
8.23 × 10²⁴ formula units × 1 mole /6.022 × 10²³ formula units
13.7 moles
Answer:
Kc = 3.94
Explanation:
CH₃COOH(g) + C₂H₅OH(g) → CH₃COOC₂H₅(g) + H₂O(g)
Liquids aren't included in the equilibrium constant, but at 100°C, all four compounds are a gas. So the equilibrium equation is:
Kc = [CH₃COOC₂H₅] [H₂O] / ([CH₃COOH] [C₂H₅OH])
Set up an ICE table for each row and calculate the value of Kc. Then average the results. (See picture.)
Kc ≈ (3.919 + 4.012 + 3.902) / 3
Kc ≈ 3.94
The question is incomplete, the complete question is:
Which statements are consistent with Dalton's atomic theory as it was originally stated? Why?
a. Sulfur and oxygen atoms have the same mass.
b. All cobalt atoms are identical.
c. Potassium and chlorine atoms combine in a 1:1 ratio to form potassium chloride.
d. Lead atoms can be converted into gold.
<u>Answer: </u>The correct options are b) and c).
<u>Explanation:</u>
Some of the postulates of Dalton's atomic theory are:
- All matter is made of very tiny particles called atoms that participate in chemical reactions
- Atoms are indivisible particles that cannot be created or destroyed in a chemical reaction
- Atoms of a given element are identical in mass and chemical properties
- Atoms of different elements have different masses and chemical properties.
- Atoms combine in the ratio of small whole numbers to form compounds.
- The relative number and kinds of atoms are constant in a given compound.
For the given options:
<u>For a:</u>
The statement is inconsistent with the theory as no two elements can have the same mass. Only atoms of the same element can have the same mass.
This is consistent with the theory as atoms of the same element are identical.
This is consistent with the theory as atoms combine in a simple whole number ratio.
The statement is inconsistent with the theory as atoms of one element cannot be changed to atoms of other element.
Hence, the correct options are b) and c).
D) blue
(about 400 nanometers)
