A 250 g sample of liquid water is initially at 15 °C
PHYSICS · Multi-part · CBSE · Physics · Thermal Properties of Matter · Thermal Properties of Matter
Problem
A 250 g sample of liquid water is initially at 15 °C. It is placed on a hot plate until its temperature reaches 60 °C. Immediately afterward, the beaker containing the water is transferred to an ice–salt bath, where the water cools to 25 °C. Assume the specific heat capacity of liquid water is 4.18 J g⁻¹ °C⁻¹ over the entire temperature range and that no water is lost to evaporation.
(a) Calculate the quantity of heat absorbed by the water while it is heated from 15 °C to 60 °C.
(b) Calculate the quantity of heat released by the water while it cools from 60 °C to 25 °C.
(c) Determine the algebraic sum of the heat changes for the two steps and state whether the water has, overall, gained or lost energy.