Chapter 3: Amount of substance

Question 1

What is a mole?

Answer 1

The amount of any substance containing as many particles as there are in an atom of carbon 12.

Question 2

What is Avagadro’s constant?

Answer 2

6.02x10^23

Question 3

What is molar mass?

Answer 3

The mass per mole of a substance in units g mol-1

Question 4

Mass, mole, Mr

Answer 4

Mole=mass/mr

Question 5

What is the molecular formula?

Answer 5

The molecular formula is the number of atoms of each element in a molecule.

Question 6

What is the empirical formula?

Answer 6

Is the simplest whole number ratio of atoms of elements in a compound

Question 7

Relative molecular mass?

Answer 7

Compares the mass of a molecule with the mass of an atom of carbon 12

Question 8

Relative formula mass?

Answer 8

Compares the mass of a formula unit with the mass of an atom of carbon-12

Question 9

Water of crystallization?

Answer 9

Water molecules that are bonded into a crystalline structure of a compound

Question 10

Hydrated compounds?

Answer 10

A crystalline compound containing water molecules

Question 11

Anhydrous salts?

Answer 11

Containing no water molecules

Question 12

Concentration, volume,mole

Answer 12

Mole=concentration x volume

Question 13

molar gas volume?

Answer 13

Is the volume per mole of gas molecules at a stated temperature and pressure

Question 14

Mole,volume,24dm^3

Answer 14

Mole=volume/24

Question 15

Ideal gas equation

Answer 15

pV=nRT

Question 16

Percentage yield?

Answer 16

%yield= actual yield/ theoretical yield x100

Question 17

The limiting reagents?

Answer 17

The reactant that is not in excess and stops the reaction from completing

Question 18

the atom economy?

Answer 18

Is a measure of how well atoms have been used in a chemical reaction
Atom economy=sum of molar masses of desired products/ sum of molar masses of all products x100