Describe two different test tube reactions to identify the following organic compounds: propanal and benzoic acid.

There are several different answers one could make and an exam question would just require one for each. 

1) Propanal - from the ending "al" this is an aldehyde.

        - Add Tollens' reagent. Positive result: Silver mirror formed.

        - Add Fehling's / Benedict Solution. Positive result: Red precipitate formed.

        - Acidified potassium dichromate. Positive result: Orange to green (due to oxidation). 

2) Benzoic acid - You probably have not come across this in the lab at school. Nevertheless from the name you can work out that it is a carboxylic acid. 

        - Add Sodium carbonate/ Sodium hydrogen carbonate. Positive result: Effervescence is observed. 

DD
Answered by Daniel D. Chemistry tutor

13665 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

How does the electronegativity of the halogen atom change as group 7 is descended?


What are the different types of intermolecular forces?


How can you tell what shape a molecule is going to be?


How to we increase the rate of a reaction?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences