# What is the mass in grams of 2.2xx10^-3 mol of Sb?

The mass of $2.2 \times {10}^{- 3} \text{mol Sb}$ is $\text{0.27 g}$.
$2.2 \times {10}^{- 3} \cancel{\text{mol Sb"xx(121.760"g Sb")/(1cancel"mol Sb")="0.27 g Sb}}$ (rounded to two significant figures)