# "State and explain" questions — Pearson Edexcel International GCSE Chemistry (4CH1)

> 10 questions · chemistry

## How to answer

"state and explain" questions from Pearson Edexcel International GCSE Chemistry (4CH1). Read the rubric carefully — the marking points cluster into scientific ideas rather than free-form prose.

## Sample questions

1. [Nitrogen has atomic number 7 and mass number 14. A different isotope of nitrogen has mass number 15. State the number of…](https://www.gradenine.co.uk/q/nitrogen-has-atomic-number-7-and-155c670e)
2. [Methane, ethane and propane are the first three members of the alkane homologous series. State the molecular formula of …](https://www.gradenine.co.uk/q/methane-ethane-and-propane-are-the-4cf2c460)
3. [A student carries out tests on an unknown solution to identify the anions present. First, dilute nitric acid is added, f…](https://www.gradenine.co.uk/q/a-student-carries-out-tests-on-599c884a)
4. [Chlorine water is added separately to two test tubes, one containing potassium bromide solution and another containing p…](https://www.gradenine.co.uk/q/chlorine-water-is-added-separately-to-5d2cad85)
5. [Lithium, sodium and potassium are all alkali metals. A student carries out flame tests on compounds of each of these met…](https://www.gradenine.co.uk/q/lithium-sodium-and-potassium-are-all-71498993)
6. [Iron has atomic number 26 and mass number 56. State the number of protons, neutrons and electrons in one atom of iron. E…](https://www.gradenine.co.uk/q/iron-has-atomic-number-26-and-8f5379eb)
7. [But-1-ene and but-2-ene are both members of the alkene homologous series and have the same molecular formula, C₄H₈. Stat…](https://www.gradenine.co.uk/q/but-1-ene-and-but-2-ene-are-both-members-b8e5c70d)
8. [Sodium has the atomic number 11 and a relative atomic mass of approximately 23. State the number of protons, neutrons an…](https://www.gradenine.co.uk/q/sodium-has-the-atomic-number-11-e0a3fe84)

## Related

- [Pearson Edexcel International GCSE Chemistry (4CH1) revision notes](https://www.gradenine.co.uk/learn/pearson-edexcel-international-gcse-chemistry-4ch1)
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