Answer the following :

A beaker contains a thick liquid. How do you test whether it is a lipid?

One can conduct an emulsion test. It is a mixture of 2 liquids which do not mix together. You can crush groundnut seeds in a test tube. Add ethyl alcohol to it. Shake it. Heat the test tube, but not directly because alcohol is flammable. When the substance dissolves, filter it dilute until you see a clear liquid. Take another test tube and pour the solution, the white suspension would mean the present of lipid.