Answer
1 kg of aluminum has more volume than 1 kg of gold.
Work Step by Step
Density = $\frac{mass}{volume}$
The smaller-density material, for the same mass, takes up more volume. To take it to extremes, imagine 1 kg of styrofoam vs. 1 kg of gold. The styrofoam takes up more volume.
This is discussed on page 230, Table 12.1.
