What mass of water at 25.0°C must be allowed to come to thermal equilibrium with a 2.20 kg gold bar at 100°C i

Question

What mass of water at 25.0°C must be allowed to come to thermal equilibrium with a 2.20 kg gold bar at 100°C in order to lower the temperature of the bar to 50.0°C?

Answer 1

Ok, you must know this :

For gold : c = 130 J / kg*K

For water : c = 4190 J / Kg*K

Now, the gold bar is at 100ºC

Water is at 25ºC

m*(50 - 25)*4190 J/Kg*K = 2.20*(100-50)*130

m = 0.136 kg = 136.5 g

Check the values for c, but they are correct, for the gold, i just look it up on the internet.