In a laboratory exercise, 200.0 g of liquid water at is mixed with an unknown mass of…
PHYSICS · Multi-part · CBSE · Physics · Thermal Properties of Matter · Thermal Properties of Matter
Problem
In a laboratory exercise, 200.0 g of liquid water at 80.0∘C is mixed with an unknown mass of liquid water that is initially at 25.0∘C. After thorough stirring in an insulated calorimeter, the mixture reaches an equilibrium temperature of 45.0∘C. No heat is absorbed by the calorimeter, and no phase change occurs. The specific heat capacity of water is 4.18Jg−1∘C−1.
(a) Calculate the mass (in grams) of the cooler water that was added.
(b) Determine the magnitude of the thermal energy released by the initially warm water as it cooled to the final temperature.
(c) Suppose that, unbeknownst to the experimenter, an additional 50.0 g of water at 25.0∘C was adhering to the inside walls of the calorimeter and was not accounted for in part (a). Explain qualitatively how this overlooked water would affect the mass of the cooler water calculated in part (a)—would the reported mass be too high, too low, or unchanged? Justify your reasoning.