# "Explain" questions — Edexcel GCSE Chemistry (1CH0)

> 108 questions · chemistry

## How to answer

WHAT + WHY. Every point paired with a because. Structure: X happens because Y. This causes Z because … Assessment Objective: AO2. Every "explain" answer on this spec is marked against exactly this pattern.

## Sample questions

1. [Explain why zinc is often used to protect iron structures, such as oil pipelines, from corrosion.](https://www.gradenine.co.uk/q/explain-why-zinc-is-often-used-00dbe882)
2. [Explain how carbon particulates produced from the incomplete combustion of fossil fuels can affect human health and the …](https://www.gradenine.co.uk/q/explain-how-carbon-particulates-produced-from-01bcd194)
3. [Explain why increasing the pressure of gaseous reactants increases the rate of reaction.](https://www.gradenine.co.uk/q/explain-why-increasing-the-pressure-of-023282bb)
4. [Explain, using particle theory, why a solid substance keeps a fixed shape but a liquid takes the shape of its container.…](https://www.gradenine.co.uk/q/explain-using-particle-theory-why-a-03b5391c)
5. [Explain why hydrogen chloride (HCl) is a gas at room temperature, whereas sodium chloride (NaCl) is a solid at room temp…](https://www.gradenine.co.uk/q/explain-why-hydrogen-chloride-hcl-is-03ea26b0)
6. [Combustion is an exothermic reaction. Explain, in terms of bond breaking and bond forming, why the temperature of the su…](https://www.gradenine.co.uk/q/combustion-is-an-exothermic-reaction-explain-0494b7b4)
7. [Silver nanoparticles are being incorporated into the fabric of some sports clothing to reduce bacterial growth and odour…](https://www.gradenine.co.uk/q/silver-nanoparticles-are-being-incorporated-into-04c518bc)
8. [Explain why potassium iodide conducts electricity when dissolved in water but does not conduct electricity when it is a …](https://www.gradenine.co.uk/q/explain-why-potassium-iodide-conducts-electricity-088302aa)

## Related

- [Edexcel GCSE Chemistry (1CH0) revision notes](https://www.gradenine.co.uk/learn/edexcel-gcse-chemistry-1ch0)
- [Edexcel GCSE Chemistry (1CH0) past papers](https://www.gradenine.co.uk/past-papers/edexcel-gcse-chemistry-1ch0)
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