Question

A vessel of mass 80 g contains 250g of water at 35degree.calculate the amount of ice at 0 degree which must be added to the vessel so the final temperature is 5 degree

Specific heat capacity of vessel : 0.8Jgk
Specific latent heat of ice : 340Jg

Answer 1

heat loss by copper vessel when temperature goes to 5 C =msdT

=50 x 0.4 (30-5)=50 x 0.4 x 25

=500 j

heat loss by water when temperature goes to 5C =msdT=250 x 4.2 x 25

=26250j

hence total heat loss=(500 +26250)

=26750 j

now ,

when ice gain heat and change its phase =mL =m x 336 j

and now ice convert in water ,

and increase temperature 5C

so, heat gain by water=m x 4.2 x 5

total heat gain=m (336 + 21)=m x 357

we know ,

heat loss =heat gain

26750=m x 357

m=74.92 gm