Calorimetry: A person makes ice tea by adding ice to 1.8 kg of hot tea, initially at 80°C. How many kilograms of ice, initially at 0.00°C, are required to bring the mixture to 10°C? The heat of fusion of ice is 334 kJ/kg, and we can assume that tea has essentially the same thermal properties as water, so its specific heat is 4190 J/(kg ∙ K).
A) 1.0 kg
B) 1.2 kg
C) 1.4 kg
D) 1.5 kg
E) 1.7 kg

Question

Quizplus · Accepted Answer

To solve this, use the principle of conservation of energy: the heat lost by the tea equals the heat gained by the ice. Calculate the heat lost by the tea as it cools from 80°C to 10°C, and equate it to the heat gained by the ice as it melts and warms to 10°C. Solving the equation gives approximately 1.4 kg of ice needed.

Calorimetry: a Person Makes Ice Tea by Adding Ice to 1.8