AQA GCSE Chemistry Foundation (8462), Foundation tier · Chemical changes › Reactions of acids
Practise Neutralisation and salt production. 6 exam-style questions on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
How acids are neutralised by alkalis, bases and metal carbonates to make salts, and how to work out the name and formula of the salt. Questions ask you to predict products, complete word and symbol equations, and work out formulae from ion charges.
Key facts
acid + alkali → salt + water
acid + metal oxide or metal hydroxide → salt + water
acid + metal carbonate → salt + water + carbon dioxide
Balance the charges so the total is zero: NaCl, MgCl2, Na2SO4, CuSO4.
Use brackets when you need more than one of an ion made of several atoms: Ca(NO3)2, Al2(SO4)3.
2NaOH + H2SO4 → Na2SO4 + 2H2O
ZnO + 2HNO3 → Zn(NO3)2 + H2O
CaCO3 + 2HCl → CaCl2 + H2O + CO2
How to answer each type of question
Name the salt and predict the products
1 to 4 marksGrade 4
Metal part of the name from the base, alkali or carbonate.
Ending from the acid: chloride, nitrate or sulfate.
Add water, and carbon dioxide too if a carbonate reacts.
Example. (a) Name the salt formed when potassium hydroxide reacts with nitric acid. (b) Name the salt formed when zinc carbonate reacts with sulfuric acid. (c) Name the other two products of the reaction in (b).
Show the model answerHide the model answer
(a) potassium nitrate (1) (b) zinc sulfate (1) (c) water (1) and carbon dioxide (1)
Don’t lose marks
Leaving out carbon dioxide or water when a carbonate reacts.
Missing brackets, e.g. writing CaNO32 instead of Ca(NO3)2.
Calling every base an alkali: only bases that dissolve in water are alkalis.
Giving hydrogen as a product of an acid and a base: hydrogen only forms when an acid reacts with a metal.
More tips
Memory tricks
Carbonate in, carbon dioxide out: any carbonate reacting with an acid fizzes and gives CO2.
Water is a product whenever an acid is neutralised by an alkali, a base or a carbonate.
Formula check: add up the charges; they must come to zero.
Exam technique
'Predict the products' means all the products, including water and carbon dioxide.
If the question gives you a formula, copy it exactly into your equation.
Decide the ending of the salt name from the acid first, then add the metal.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 3
Name the salt type from each acidHydrochloric acid gives chlorides, nitric acid gives nitrates and sulfuric acid gives sulfates.
Grade 4
Predict products of acid with base or alkaliacid + metal oxide or metal hydroxide → salt + water.
Grade 4
Predict products of acid with a carbonateacid + metal carbonate → salt + water + carbon dioxide.
Grade 5
Tell the difference between bases and alkalisA base neutralises an acid; an alkali is a base that dissolves in water, such as a soluble metal hydroxide.
Quick recall
Cover the answers and test yourself. The app has these as flashcards that come back just before you'd forget them.
Name the salt produced when sodium hydroxide reacts with nitric acid.
sodium nitrate
Write a balanced symbol equation for the reaction of zinc carbonate, ZnCO3, with sulfuric acid.
ZnCO3 + H2SO4 → ZnSO4 + H2O + CO2
Name the salt formed when potassium hydroxide reacts with hydrochloric acid.
potassium chloride
Write the general word equation for the reaction between a metal carbonate and an acid.
metal carbonate + acid → salt + water + carbon dioxide
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy4 marks
Acids react with bases, alkalis and carbonates to produce salts.
(a) Name the salt produced when sodium hydroxide reacts with nitric acid.[1]
(b) Name the salt produced when copper oxide reacts with sulfuric acid.[1]
(c) What are the products when calcium carbonate reacts with hydrochloric acid? Tick (✓) one box.[1]
calcium chloride and water only
calcium chloride, water and carbon dioxide
calcium chloride and hydrogen
calcium hydroxide and carbon dioxide
(d) Which acid produces salts called chlorides?[1]
Show the answer and mark scheme
(a)Answer: sodium nitrate
sodium nitrate
(b)Answer: copper sulfate
copper sulfate / copper(II) sulfate
(c)Answer: calcium chloride, water and carbon dioxide
(d)Answer: hydrochloric acid
hydrochloric acid
Question 2Medium5 marks
Metal oxides, metal hydroxides and metal carbonates all neutralise acids.
(a) What is the difference between a base and an alkali?[1]
(b) Write a balanced symbol equation for the reaction of zinc carbonate, ZnCO3, with sulfuric acid.[2]
(c) Describe what you would see when green copper carbonate powder is added to dilute hydrochloric acid until no more reacts.[2]
Show the answer and mark scheme
(a)
an alkali is a base that dissolves in water / an alkali is a soluble base (e.g. a soluble metal hydroxide)