m=11.151
For this question, we have to remember that
[tex]d=\frac{m}{V}[/tex]So, if the density's been given let's plug in the rest since the units are already properly adjusted.
[tex]\begin{gathered} 2.1=\frac{m}{5.31}\text{ } \\ m\text{ = 2.1 }\cdot5.31 \\ m=11.151\text{ g} \end{gathered}[/tex]So the mass of 11.151g is enough to yield such density.
