Relative formula mass (FT only)

This lesson will recap briefly on relative atomic mass and students will calculate relative formula mass and percentage composition of an element in a compound.

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Relative formula mass

This quiz will test your knowledge from this lesson.

Question 1

Question 2

Question 3

Question 4

Question 5

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.The formula of magnesium sulfate is MgSO₄. Calculate the relative formula mass of magnesium sulfate. Relative atomic masses: Mg = 24; S= 32; O = 16.

2/5

Q3.Calculate the relative formula mass of iron oxide, Fe₂O₃. Relative atomic masses: O = 16; Fe = 56.

3/5

Q4.A chemist was asked to identify a nitrogen compound. The chemist carried out an experiment to find the relative formula mass (Mr) of the compound. The Mr of the compound was 44. Relative atomic masses: N = 14; O = 16. What is the formula of the compound?

4/5

Q5.Calculate the percentage of O in Be(OH)₂. Be = 9; O = 16; H = 1.

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Relative formula mass

This quiz will test your knowledge from this lesson.

Question 1

Question 2

Question 3

Question 4

Question 5

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.The formula of magnesium sulfate is MgSO₄. Calculate the relative formula mass of magnesium sulfate. Relative atomic masses: Mg = 24; S= 32; O = 16.

2/5

Q3.Calculate the relative formula mass of iron oxide, Fe₂O₃. Relative atomic masses: O = 16; Fe = 56.

3/5

Q4.A chemist was asked to identify a nitrogen compound. The chemist carried out an experiment to find the relative formula mass (Mr) of the compound. The Mr of the compound was 44. Relative atomic masses: N = 14; O = 16. What is the formula of the compound?

4/5

Q5.Calculate the percentage of O in Be(OH)₂. Be = 9; O = 16; H = 1.

5/5

Lesson summary: Relative formula mass (FT only)

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