Question

What mass of water at 25.0°C must be allowed to come to thermal equilibrium with a 1.85kg cube of aluminum initially at 1.50 x 102 °C to lower the temperature of the aluminum to 65.0°C? Assume any water turned to steam subsequently recondenses.

Answer 1

m_w = mass of water = ?

c_w = specific heat of water = 4186 J/(kg C)

T_wi = initial temperature of water = 25 C

T_wf = final temperature of water = 65 C

m_c = mass of cube = 1.85 kg

c_c = specific heat of cube = 900 J/(kg C)

T_ci = initial temperature of cube = 150 C

T_cf = final temperature of cube = 65 C

using conservation of heat

Heat gained by water = heat lost by cube

m_w c_w (T_wf - T_wi ) = m_c c_c (T_ci - T_cf)

m_w (4186) (65 - 25) = (1.85) (900) (150 - 65)

m_w = 0.85 kg