Practical: making and testing the smell of some esters in the lab
2 marks · NormalState the name of the acid catalyst used in the laboratory preparation of esters, and explain why direct heating with a Bunsen burner should not be used in this experiment.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
Also accept: acid catalyst: concentrated sulphuric acid; reason: the mixture is flammable / must not be heated with a naked flame; acid catalyst: conc. H2SO4; reason: esters or reactants are highly flammable
Common mistakes: Naming acetic acid as catalyst; Saying 'to make it react better' only
Show mark scheme and worked solution
Marking points
B1 · 1 mark · States concentrated sulfuric acid (or conc. H2SO4) as the acid catalyst.
B2 · 1 mark · Explains that direct heating is avoided because the reactants/product are flammable or must not be heated with a naked flame.
Worked solution
The acid catalyst used is concentrated sulfuric acid.
Direct heating with a Bunsen burner should not be used because the mixture contains flammable substances and could catch fire.