Question

Explain why your hand feels cold when you drop some petrol on it

Answer 1

Answer:

Petrol is a highly inflammable, and volatile liquid.

By the term "volatile" , it is meant that the liquid undergoes evaporation instantaneously at room temperature.

Now, if petrol is dropped on the hand , petrol takes up its specific latent heat from the surroundings in the hand , thereby getting converted to gaseous state.

Since the specific latent heat is taken up by petrol, the hand feels cool.

Specific latent heat is the amount of energy required by a substance in liquid state to undergo conversion to gaseous state .

Answer 2

Acetone,petrol and perfume are volatile substance that gets evaporated when they come in contact with air Evaporation is facilitated as it uses energy from the palm hence leaving a cooling effect on our palms.