Moles

Question 1

What is the mass of one mole of carbon?

Answer 1

12 grams

Question 2

What volume does 1 mole of oxygen gas occupy?

Answer 2

24 dm³ or 24 000 cm³

All gases occupy the same volume per mole of 24 dm³ per mole

Question 3

How many atoms are there in a mole of substance?

Answer 3

6.02 x 10²³ atoms

This is called Avogadro’s number

Question 4

How many molecules are there in 2 moles of oxygen?

What volume will this occupy?

Answer 4

2 x 6.03 x 10²³ molecules

OR 12.6 x 10²³ molecules

This would occupy 2 x 24 dm³

OR 48 dm³ of space

Question 5

What is the mass of 2 moles of carbon?

Answer 5

2 x 12 g/mol = 24 g

Question 6

What does the symbol A_r stand for?

Answer 6

Relative atomic mass - relative mass of one atom of an element compared to the mass of one atom of carbon-12

Question 7

What is a mole?

Answer 7

The measure of amount of substance

Question 8

What is molar mass?

Answer 8

The molar mass is the relative formula mass (RFM) of a substance, measured in g/mol

Question 9

How is molecular mass different from molar mass (relative formula mass)

Answer 9

Molecular mass is the relative mass of one molecule of a substance measure relative to carbon-12 just like realtive atomic mass is the relative mass of one atom of an element

However, molar mass or relative formula mass is the mass of one mole of that substance measured in g/mol.

Question 10

What does M_r stand for?

Answer 10

Relative molecular mass- mass of one molecule of a substance compared to carbon-12

Question 12

What is a molar volume?

Answer 12

The volume one mole of any gas occupies as RTP

24 dm³ or 24 000 dm³