a) In a reaction, 2-methylbutan-1-ol is oxidised by potassium dichromate. Write equations for the two oxidation steps of this reaction.

Question

Then name and draw (as displayed formula) the two products of this reaction.

b) One of the products gives a silver mirror when warmed with Tollen’s reagent. State the identity of this product and name the functional group that this product belongs to.

Answer 1

2-methylbutan-1-ol + [O] ==> 2-methylbutan-1-al + water
CH3CH2CH(CH3)CH2OH + [O] ==> CH3CH2CH(CH3)CHO + H2O
second step:
CH3CH2CH(CH3)CHO + [O] ==> CH3CH2CH(CH3)COOH
2-methylbutan-1-al + [O] ==> 2-methylbutanoic acid
b) Tollen's reagent is a basic solution of the silver amine complex ion. A positive test is exhibited by a precipitation of silver, often as a "mirror" on the inside of the reaction vessel (my personal experience is I NEVER got a mirror test but a black solution of colloidal silver metal). The aldehyde provides the positive test.

Answer 2

For part b:

What is the identity of the product?

What is the functional group that this product belongs to?

Answer 3

As I stated in my answer the aldehyde is the functional group. in this case it's the 2-methylbutan-1-al

Answer 4

Draw (as displayed formula) the two products of this reaction.