A piece of gold with a mass of 15.23 g and an initial temperature of 54 °C was dropped into a calorimeter containing 28 g of water. The final temperature of the metal and water in the calorimeter was 62°C. What was the initial temperature of the water?

31.03 °C

62.13 °C

81.03°C

92.13°C

A piece of gold with a mass of 15.23 g and an initial temperature of 54 °C was dropped into a calorimeter containing 28 g of water. The final temperature of the metal and water in the calorimeter was 62°C. this can be solve using the formula H = mCpDeltaT where m is the mass, Cp is the heat capacity, delta T is the change in temperature

Cp of gold = 0.129 J / g °C

Cp of water = 4.18 J / g °C

The H for both are equal, so equate them and solve for the initial T of water

(15.23g) (0.129 J / g C) (62 °C - 54 °C) = (28 g) (4.18 J / g °C) (Ti - 62 °C)

Ti = 62.13 °C