Chemical Changes | AQA GCSE Chemistry, Foundation tier (8462)
Chemical Changes
- 146 questions
- 9 subtopics
- Paper 1
- Paper 1
Chemical Changes is examined in Chemistry Paper 1.
It covers the reactivity series, metal oxides, extraction, and oxidation and reduction in terms of oxygen, acids reacting with metals, neutralisation and salts, soluble salts, the pH scale and neutralisation, titrations, the process of electrolysis, and molten ionic compounds, using electrolysis to extract metals and electrolysis of aqueous solutions.
Sample questions from Chemical Changes
Answer each one closed book first, then open the answer.
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The reactivity series
State the rule that decides whether one metal will take another metal's place in a compound.
Show the answer
A more reactive metal displaces a less reactive metal from its compound. -
Metal oxides, extraction, and redox in terms of electrons
Why is gold found in the Earth as the metal itself?
Show the answer
Gold is so unreactive that it does not combine with other elements to form compounds. -
Acids reacting with metals, neutralisation and salts
Write the balanced equation for magnesium reacting with dilute hydrochloric acid.
Show the answer
Mg + 2HCl → MgCl₂ + H₂. -
Soluble salts
How is a solid salt obtained from a solution of that salt?
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The solution is crystallised. -
The pH scale and neutralisation
What is the full range of the pH scale?
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It runs from 0 to 14. -
Titrations
Which piece of apparatus measures the fixed volume of alkali placed in the conical flask?
Show the answer
A pipette used with a pipette filler. -
The process of electrolysis, and molten ionic compounds
What is electrolysis?
Show the answer
Passing an electric current through an electrolyte so that ions are discharged at the electrodes, producing elements. -
Using electrolysis to extract metals
Which compound is aluminium extracted from?
Show the answer
Aluminium oxide.
The 9 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| The reactivity series | Metals forming positive ions and reactivity as the tendency to do so, the series from potassium to copper with hydrogen and carbon for comparison, displacement reactions, ordering metals by their reactions with water and dilute acid in a fair test, and why potassium reacts more vigorously than magnesium. | 20 |
| Metal oxides, extraction, and redox in terms of electrons | Metal oxides and oxidation and reduction in terms of oxygen, why gold is found as the metal, extracting metals less reactive than carbon by heating their oxides with carbon as the reducing agent, comparing industrial extraction methods, and predicting which oxides carbon can reduce. | 15 |
| Acids reacting with metals, neutralisation and salts | Metals reacting with dilute acids to give a salt and hydrogen, word and balanced equations and the test for hydrogen, neutralisation of acids by alkalis, bases and metal carbonates, the difference between a base and an alkali, naming salts from their acids, and deducing salt formulae from their ions. | 16 |
| Soluble salts | Making a soluble salt by adding an insoluble metal, oxide, hydroxide or carbonate to an acid in excess, filtering off the unreacted solid, crystallising and drying the salt, the copper sulfate preparation, choosing gentle heating, safety precautions, and why crystals can lose mass. | 16 |
| The pH scale and neutralisation | Hydrogen ions in acids and hydroxide ions in alkalis, aqueous solutions, the pH scale from 0 to 14 measured with universal indicator or a pH probe, acidic, neutral and alkaline values, and neutralisation as hydrogen ions reacting with hydroxide ions to form water, with its ionic equation. | 18 |
| Titrations | What a titration measures and why an indicator is needed, the pipette and burette, the three acids used, adding acid drop by drop near the end point, concordant titres, the white tile and rinsing, working out the titre from burette readings, and why the first titration is a rough one. | 14 |
| The process of electrolysis, and molten ionic compounds | Electrolytes and why molten or dissolved ionic compounds conduct, electrolysis and the cathode and anode, which ions move to each electrode, inert electrodes, and predicting the products of electrolysing molten lead bromide, sodium chloride and zinc bromide. | 14 |
| Using electrolysis to extract metals | When electrolysis is used to extract a metal, why the compound must be molten and why the process is costly, and the extraction of aluminium from aluminium oxide mixed with cryolite using carbon anodes that burn away. | 15 |
| Electrolysis of aqueous solutions | Which ions are present in a solution, how relative reactivity decides whether the metal or hydrogen forms at the cathode, when oxygen or a halogen forms at the anode, predicting products, and testing the gases collected. | 18 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
AQA GCSE Chemistry, Foundation tier Active Recall Guide
Every topic, not just this one. 1,386 questions with their answers.