Question

2)Why is ice at 273 k more effective in cooling than water at
the same temperature?​

Answer 1

Ice at 273K is more effective in cooling than water at the same temperature as ice takes latent heat from the substances for melting and hence cools the substances more effectively than water at the same temperature.

Answer 2

Answer:

It is due to latent heat of fusion. Ice at 273 k has less energy than water at 273 k. The reason water has more energy but its temperature is same is because the energy provided to it was  used in changing the state. This also the same reason why steam gives more severe burn than water at 373 k ( in this case it would be called latent heat if vaporization ).

Hope this helps :)