Aqueous NaBH4\text{NaBH}_4NaBH4 reduces aldehydes but does not reduce alkenes.
Show the first step of the mechanism of the reaction between NaBH4\text{NaBH}_4NaBH4 and 3-methylbutanal. You should include two curly arrows.
Explain why NaBH4\text{NaBH}_4NaBH4 reduces 3-methylbutanal but has no reaction with 3-methylbut-1-ene.
A student attempted to reduce a sample of 3-methylbutanal but added insufficient NaBH4\text{NaBH}_4NaBH4. The student confirmed that the reduction was incomplete by using a chemical test.
Give the reagent and observation for the chemical test.
14 exam-style questions on AQA A Level Chemistry Aldehydes and ketones (A-level only), covering Aldehydes and ketones (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.