# What is the molar mass of CaSO_4?

${M}_{C a S {O}_{4}} = 136.13400 \frac{g}{m o l}$
${M}_{C a S {O}_{4}} = 40.078 \frac{g}{m o l} + 32.06 \frac{g}{m o l} + 4 \cdot 15.999 \frac{g}{m o l}$
$= 136.13400 \frac{g}{m o l}$