# Moles and Avogadro's constant (HT only)

This lesson, students will use the equation mass = relative formula mass x moles to find any one value when given the other two. Students will use Avogadro's constant to calculate the number of atoms/molecules in a given mass and also calculate the mass of a given number of atoms.

Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.The formula of sodium chloride is NaCl. Calculate the relative formula mass of sodium chloride. Relative atomic masses: Na = 23; Cl = 35.5

1/5

Q2.Calculate the relative formula mass of iron oxide, Fe₂O₃. Relative atomic masses: O = 16; Fe = 56.

2/5

Q3.Calculate the percentage of O in Be(OH)₂. Be = 9; O = 16; H = 1

3/5

Q4.A metal oxide has a relative formula mass (Mr) of 81. The formula of this metal oxide is XO. The relative atomic mass (Ar) of oxygen is 16. Calculate the relative atomic mass (Ar) of metal X.

4/5

Q5.What is the name of the metal X (from the question above)?

5/5

Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.The formula of sodium chloride is NaCl. Calculate the relative formula mass of sodium chloride. Relative atomic masses: Na = 23; Cl = 35.5

1/5

Q2.Calculate the relative formula mass of iron oxide, Fe₂O₃. Relative atomic masses: O = 16; Fe = 56.

2/5

Q3.Calculate the percentage of O in Be(OH)₂. Be = 9; O = 16; H = 1

3/5

Q4.A metal oxide has a relative formula mass (Mr) of 81. The formula of this metal oxide is XO. The relative atomic mass (Ar) of oxygen is 16. Calculate the relative atomic mass (Ar) of metal X.

4/5

Q5.What is the name of the metal X (from the question above)?

5/5

# Video

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# Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

Quiz:

# Moles and Avogadro's constant - Higher

This quiz will test your knowledge from this lesson and previous lessons

Q1.What is a mole?

1/9

Q2.Which equation would you use to calculate mass?

2/9

Q3.Calculate the mass of 1.5 moles of MgSO₄. Relative atomic mass of Mg = 24; S = 32; O 16

3/9

Q4.Convert 0.72 kg into grams.

4/9

Q5.Convert 648 mg into grams.

5/9

Q6.Calculate the number of moles in 6.6 kg of NaCl. Relative atomic mass Na = 23; Cl = 35.5

6/9

Q7.How many atoms or molecules in a mole?

7/9

Q8.Calculate the number of atoms in 46 g of Na. (Hint - calculate the number of moles first). Relative atomic mass Na = 23.

8/9

Q9.Calculate the number of atoms in 5 moles H₂O.

9/9

Quiz:

# Moles and Avogadro's constant - Higher

This quiz will test your knowledge from this lesson and previous lessons

Q1.What is a mole?

1/9

Q2.Which equation would you use to calculate mass?

2/9

Q3.Calculate the mass of 1.5 moles of MgSO₄. Relative atomic mass of Mg = 24; S = 32; O 16

3/9

Q4.Convert 0.72 kg into grams.

4/9

Q5.Convert 648 mg into grams.

5/9

Q6.Calculate the number of moles in 6.6 kg of NaCl. Relative atomic mass Na = 23; Cl = 35.5

6/9

Q7.How many atoms or molecules in a mole?

7/9

Q8.Calculate the number of atoms in 46 g of Na. (Hint - calculate the number of moles first). Relative atomic mass Na = 23.

8/9

Q9.Calculate the number of atoms in 5 moles H₂O.

9/9

# Lesson summary: Moles and Avogadro's constant (HT only)

## Time to move!

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For 5 mins...

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