1. CHEMISTRY – summer assignment
Question 1
2Na + H2SO4 → Na2SO4 + H2
What is the relative formula mass of sodium sulphate, Na2SO4?
What is the percentage by mass of sodium in sodium sulphate, Na2SO4?
What is the mass of 1 mole of sulphuric acid, H2SO4?
What is the percentage by mass of sulphur in sulphuric acid, H2SO4?
Calculate the mass of sodium sulphate that can be made from 24.5g of sulphuric acid
Calculate the mass of sodium sulphate that can be made from 69g of sodium
Question 2
Carbon-12 (12C) and carbon-13 (13C) are the two main isotopes of carbon.
What is an isotope?
How is an atom of 12C similar to an atom of 13C?
How is an atom of 12C different to an atom of 13C?
Question 3
What is the empirical formula of the compound which contains 0.60g of magnesium and 4.00g of bromine?
What is the empirical formula of sodium oxide that contains 74.19% sodium?
Question 4
In a reaction, the predicted yield was 80g, but the actual yield was 50g. What is the percentage yield?
What is the percentage yield if the actual yield was 2.4g and the predicted yield was 3.0g?
State 2 reasons why percentage yield is usually less than 100%
Question 5
Design a guide to writing balanced chemical equations, aimed at a student in Year 10 who is meeting this topic for the first time.
Using the complete combustion of methane as your example reaction, explain how to write word equations and how to write balanced chemical equations, including state symbols.
Create at least two practice questions with model answers that would allow the Year 10 student to check their understanding of writing balanced equations.