Question

What quantity of heat must be removed from 20gof water at 0°C to change it to ice at 0°C?​

Answer 1

The quantity of heat must be removed is 1600 cal or 1,6 kcal.

Explanation :

From the question we will know if the condition of ice is at the latent point. So, the heat level not affect the temperature, but it can change the object existence. So, for the formula we can use.

$\boxed {\bold {Q = m \times L}}$

If :

• Q = heat of latent (cal or J )
• m = mass of the thing (g or kg)
• L = latent coefficient (cal/g or J/kg)

Steps :

If :

• m = mass of water = 20 g => its easier if we use kal/g°C
• L = latent coefficient = 80 cal/g

Q = ... ?

Answer :

$Q = m \times L \\ Q = 20 \times 80 = 1600 \: cal$

So, the quantity of heat must be removed is 1600 cal or 1,6 kcal.

Subject : Physics

Subject : Physics Keyword : Heat of latent