# "Explain" questions — OCR A-Level Chemistry B: Salters (H433)

> 103 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. [Dmitri Mendeleev arranged elements into a periodic table in 1869. The modern periodic table is arranged in order of atom…](https://www.gradenine.co.uk/q/dmitri-mendeleev-arranged-elements-into-a-007abba8)
2. [Explain why the majority of plastics used in everyday products are difficult to dispose of responsibly, and describe one…](https://www.gradenine.co.uk/q/explain-why-the-majority-of-plastics-0083d136)
3. [A doctor is explaining to a medical student how the human body is made from a small number of chemical elements. The doc…](https://www.gradenine.co.uk/q/a-doctor-is-explaining-to-a-00cd53a8)
4. [A fashion designer is developing a new range of clothing and wants to use natural dyes instead of synthetic dyes. Explai…](https://www.gradenine.co.uk/q/a-fashion-designer-is-developing-a-018a21e0)
5. [Propan-1-ol and 1-chloropropane are two organic compounds. Explain how a chemist could distinguish between propan-1-ol a…](https://www.gradenine.co.uk/q/propan-1-ol-and-1-chloropropane-are-two-organic-079a08af)
6. [Explain why the oceans contain dissolved salts and describe how the concentration of these dissolved salts affects marin…](https://www.gradenine.co.uk/q/explain-why-the-oceans-contain-dissolved-0a0225bc)
7. [Explain why elements in the same group of the periodic table have similar chemical properties, and describe how the reac…](https://www.gradenine.co.uk/q/explain-why-elements-in-the-same-16f97ae1)
8. [A student uses a reaction profile to compare two reactions: an uncatalysed decomposition of hydrogen peroxide and the sa…](https://www.gradenine.co.uk/q/a-student-uses-a-reaction-profile-1f99baf5)

## Related

- [OCR A-Level Chemistry B: Salters (H433) revision notes](https://www.gradenine.co.uk/learn/ocr-a-level-chemistry-b-salters-h433)
- [OCR A-Level Chemistry B: Salters (H433) past papers](https://www.gradenine.co.uk/past-papers/ocr-a-level-chemistry-b-salters-h433)
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