The picture below shows an investigation of the properties of substances.
The red litmus paper is dipped in a solution.
The litmus paper turns blue when dipped in a/an \(\underline{\hspace{2cm}}\) solution.
Irfan ran out of litmus paper to test for acidic and alkaline substances.
Which material can replace the litmus paper?
A wasp sting is alkaline.
Which substance would neutralise the sting?
There is something wrong with this question.