Amount of Substance

Question 1

What does it mean by amount of a substance?

Answer 1

Has an SI unit of mole

Question 2

What is a mole?

Answer 2

The amount of a substance compared with 12g for Carbon-12.

Question 3

What is the Avogadro Constant?

Answer 3

6.02x10²³ mol^-1. It is the amount of atoms in one mole of the substance.

Question 4

What is molar mass?

Answer 4

mass/moles

Question 5

What is molar gas volume?

Answer 5

24dm³

Question 6

What is an empirical formula?

Answer 6

The simplest whole number ratio of atoms of each element present in a compound

Question 7

What is a molecular formula?

Answer 7

the number and type of atoms of each element in a molecule

Question 8

How do you calculate empirical formula?

Answer 8

Work out the moles of each atom and the ratio between them

Question 9

How do you calculate molecular formula?

Answer 9

Work out the empirical formula and multiply by n to achieve the same mass etc needed

Question 10

What does anhydrous mean?

Answer 10

substance containing no water

Question 11

What does hydrated mean?

Answer 11

substance that contains water

Question 12

What are water of crystallisation?

Answer 12

water molecules that form an essential part of the structure of the compound (e.g X.5H₂O)

Question 13

How do you calculate water of crystallisation?

Answer 13

Use relative formula masses

Question 14

What is an equation linking moles, concentration and volume?

Answer 14

n=cv

Question 15

What is the ideal gas equation?

Answer 15

PV=nRT

R=8.314

Question 16

How do you calculate percentage yield?

Answer 16

(actual yield/percentage yied) x 100

Question 17

How do you calculate atom economy?

Answer 17

(mass of atoms of desired product/mass of atoms of reactants) x 100

Question 18

What are the benefits for sustainability for developing chemical processes with high atom economy?

Answer 18

.