Assertion : If one gram of ice is mixed with `1 g` of water at `80^(@)C`, then the final temperature of mixture is zero.
Reason : Latent heat of ice `80^(@) cal//g`

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If the assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

B

Explanation

Heat required by ice to melt.
`=1xx80=80 cal`.
Heat lost by water in cooling from `80^(@)C` to `0^(@)C`
`=1xx1xx(80-0)=80cal`.
From principal of calorimetry,
Heat lost = Heat gained.