27.0 g
Explanation:
The density of a substance tells you the mass of exactly one unit of volume of said substance.
In your case, aluminium is said to have a density of
density Al
=
2.70 g
.
cm
−
3
This tells you that every
1 mL
of aluminium has a mass of
2.70 g
.
All you have to do now is use the density of aluminium as a conversion factor to go from cubic centimenters of aluminium to grams
10.0
cm
3
⋅
2.70 g
1
cm
3
=
27.0 g
−−−−−
The answer is rounded to three sig figs.