In order to raise the temperature of 5.0 Kg of water from 20 deg. C to 30 deg. C, a 2.0 kg iron bar is heated and then dropped into the water. What should the starting temperature of the bar be? (Specific heat Fe is 0.22 cal/g-deg.)

Question

In order to raise the temperature of 5.0 Kg of water from 20 deg. C to 30 deg. C, a 2.0 kg iron bar is heated and then dropped into the water.  What should the starting temperature of the bar be?  (Specific heat Fe is 0.22 cal/g-deg.)

DrBob222 · Answer

I may have answered this for you already but here it is again.
heat lost by Fe bar + heat gained by water = 0

[mass Fe x specific heat Fe x (Tfinal-Tinitial)] + [mass water x specific heat water x (Tfinal-Tinitial)] = 0
Solve for spcific heat Fe, the only unknown.