Calculating Heat Transfer in Melting Ice: A Thermochemistry Problem

[ThePageHendrix]

Homework Statement

If 13.4 kJ of heat is added 1.00 kg of ice at 0ºC, how much ice will be melted

Homework Equations

Change of Heat = mass*change of temperature*constant

change of heat fusion (water) = 333 J/g

change of heat water vapor = 2260 J/g

change of heat total = change of heat (state) + change of heat (temp change)

constant of water = 4.184 J/gºC

constant of ice = 2.1 J/gºC

The Attempt at a Solution

(1000g)(2.1J/gºC)(?-0) + (13400g*333J/gºC)

Answer = 40g

 

[Chestermiller]

Hi ThePageHendrix. Welcome to Physics Forums!

If it takes 333 kj to melt the entire 1 kg of ice, how much ice will only 13.4 kj melt?

Chet

 

[ThePageHendrix]

Thanks for answering!

Sorry, but it takes 333 joules, not kj, to melt the ice. I'm sorry, but I am just really lost on how to approach this problem.

Any more help is appreciated, thanks!

 

[Chestermiller]

Thanks for answering!

Sorry, but it takes 333 joules, not kj, to melt the ice. I'm sorry, but I am just really lost on how to approach this problem.

Any more help is appreciated, thanks!

It takes 333J to melt 1 gm; it takes 333kJ to melt 1 kg.

 

[Borek]

Change of Heat = mass*change of temperature*constant

This equation describes amount of heat when dealing with the temperature change. When the ice melts, temperature doesn't change (in such cases we say it is a "latent heat"). Latent heat requires different equation. Chet already pointed you at the intuition behind the other equation you need.