A 10.0 gram piece of metal is placed in an insulated calorimeter containing 250.0 g of water initially at 20.0°C. If the final temperature of the mixture is 25.0°C, what is the heat change of water?

A) 5230 J

B) −5230 J

C) 209 J

D) −209 J

E) 5440 J

Question

A 10.0 gram piece of metal is placed in an insulated calorimeter containing 250.0 g of water initially at 20.0°C. If the final temperature of the mixture is 25.0°C, what is the heat change of water?
		
A) 5230 J
		
B) −5230 J
		
C) 209 J
		
D) −209 J
		
E) 5440 J

anonymous · Answer

Q = m cp dT

anonymous · Answer

i got 5230 J but why is there a negative option?

cuanchi · Answer

because if you consider the heat change of the iron in place of the heat change of the water the dT will be negative and the Q will be negative. The iron is giving heat to the water. In this case the iron was warmer than the water.