Question

A cube of aluminum (Cp = 0.897 J/g•K) has a temperature of 325 K. It is placed in a beaker of cold water. If the aluminum cools to 301 K as the water absorbs 815.7 J of heat, what is the mass of the cube?

Use the formula q = mCes002-1.jpges002-2.jpgT.

g

Answer 1

q (absorbed by water) = -q (lost by Al) = 815.7 J. Use |q| = m C ΔT with ΔT = 325 − 301 = 24 K.

m = |q| / (C ΔT) = 815.7 J / (0.897 J·g⁻¹·K⁻¹ × 24 K)
= 815.7 / 21.528 ≈ 37.9 g.

So the cube's mass is about 37.9 g (≈0.0379 kg).