colorless flammable boils at 78°C density of 0.79 g/cm^3
I gave my students this multiple choice question: Which of the following properties of ethanol is a chemical property?

Only one answer is correct among these 4 choices:
- colorless
- flammable
- boils at 78°C
- density of 0.79 g/cm^3

Could you tell me which one is correct?

flammable