Chapter 3, Amount Of Substance And The Mol

Question 1

What is the unit for mols in a substance?

Answer 1

gmol‐¹

Question 2

What is the equation to work out mols?

Answer 2

Mol = mass ÷ Mr

Question 3

Give the equation to work out number of particles?

Answer 3

Number of particles = mols × avagdro’s constant

Question 4

What is the value of avagadro’s constant?

Answer 4

6.02×10²³

Question 5

What is molecular formula?

Answer 5

The actual number of each atom in a compound

Question 6

What is empirical formula?

Answer 6

The simplist whole number ratio of each atom in a compound

Question 7

Find the empirical formula of the compound containing 72.4% Fe and 27.6% O

Answer 7

Fe O
72.4 ÷ 27.6 ÷
55.8 = 16.0 =
1.30 ÷ 1.73 ÷ FeO
1.30 = 1.30 = 4
1 4

Question 8

Give the equation which includes mols, concentration and volume

Answer 8

Mols = concentration (mol/dm³) × volume (dm³)

Question 9

What are the RTP values?

Answer 9

101,000 pa
293k

Question 10

Give the RTP equation

Answer 10

Mols = volume (dm³) ÷ 24

Question 11

What is the ideal gad equation?

Answer 11

PV = nRT

Question 12

Calculate the amount of aluminium that can be formed from 1020g of aluminium oxide

Answer 12

Al O : Al
2 3

2:4
10:20

Mass = mol × Mr
540 = 20 × 27.0