An exercise I have problems with:

 

In a thermos bottle with heat capacity 90 J/K there is 0.4 kg water. The temperature of the water and the thermos bottle is 313 K. Brass with mass 0.1 kg has temperature 363 K and specific heat capacity 380 J/(kg *K). It is dropped into the thermos bottle.

a) What will the temperature of the water be?

 

b) 0.02 kg ice with temperature 273 K is added. What will the temperature of the water be now?

 

I presume that no heat will leak from the thermos bottle.

I think I will manage a), but b) is more difficult. Help will be appreciated.

Show your work. Part b requires you account for the phase change in the ice, by using latent heat.

I will try on part b. Can this be correct?

 

q*m is the energy needed to melt ice

C is heat capacity

c is spcific heat capacity

m=mass

T=temperature

i=ice w=water t=thermos bottle b=brass

Looks right.