In: Physics
Suppose 28.0 g of ice at -10.0∘C is placed into 300.0 g of water in a 200.0-g copper calorimeter. The final temperature of the water and copper calorimeter is 18.0∘C.
1) What was the initial common temperature of the water and copper? (Express your answer to three significant figures.)
Specific heat of water = C1 = 4186 J/(kg.oC)
Specific heat of copper = C2 = 385 J/(kg.oC)
Specific heat of ice = C3 = 2100 J/(kg.oC)
Latent heat of fusion of water = L = 3.34 x 105 J/kg
Mass of the water = m1 = 300 g = 0.3 kg
Mass of the copper calorimeter = m2 = 200 g = 0.2 kg
Mass of the ice = m3 = 28 g = 0.028 kg
Initial temperature of the water and copper calorimeter = T1
Initial temperature of ice = T2 = -10 oC
Melting point of ice = T3 = 0 oC
Final equilibrium temperature = T4 = 18 oC
Heat removed from the water to take it to 18 oC = Q1
Q1 = m1C1(T1 - T4)
Heat removed from the copper calorimeter to take it to 18 oC = Q2
Q2 = m2C2(T1 - T4)
Heat added to the ice to take it to 18 oC = Q3
Q3 = m3C3(T3 - T2) + m3L + m3C1(T4 - T3)
The heat removed from the water and the copper calorimeter is equal to the heat added to the ice.
Q1 + Q2 = Q3
m1C1(T1 - T4) + m2C2(T1 - T4) = m3C3(T3 - T2) + m3L + m3C1(T4 - T3)
(0.3)(4186)(T1 - 18) + (0.2)(385)(T1 - 18) = (0.028)(2100)(0 - (-10)) + (0.028)(3.34x105) + (0.028)(4186)(18 - 0)
1255.8T1 - 22604.4 + 77T1 - 1386 = 588 + 9352 + 2109.744
1332.8T1 = 36040.144
T1 = 27.0 oC
1) Initial common temperature of the water and copper calorimeter = 27.0 oC