A Lab Assistant Drops a 400 $15.0 ^ { \circ } \mathrm { C }$

Multiple Choice

A lab assistant drops a 400.0-g piece of metal at 100.0°C into a 100.0-g aluminum cup containing 500.0 g of water at $15.0 ^ { \circ } \mathrm { C }$ In a few minutes, she measures the final temperature of the system to be 40.0°C. What is the specific heat of the 400.0-g piece of metal, assuming that no significant heat is exchanged with the surroundings? The specific heat of this aluminum is 900.0 J/kg ? K and that of water is 4186 J/kg ? K.

A) 1900 J/kg ? K
B) 2270 J/kg ? K
C) 3300 J/kg ? K
D) 3800 J/kg ? K
E) 4280 J/kg ? K