## Chemistry and Chemical Reactivity (9th Edition)

$50 \ mg$
We are given the density and the volume ($V=0.50\ mL,\ \rho=1.0\ g/mL$), so the total mass is: $m=0.50\times1.0 = 0.50\ g$ Since the solution contains 10% by mass of the compound: $m_c=0.50\times0.10=0.050\ g$ $0.050\ g \times \dfrac{1\ mg}{1\times10^{-3}\ g}=50 \ mg$