Question

What is the molarity of a solution when 157g of CaSO4 are dissolved in enough water to yield a volume of 724ml

Answer 1

M(CaSO₄) = 136.14 g/mol

$n=\frac{m}{M} \\ = \frac{157}{136.14}=1.153 \;mol$

Proportion:

1.153 mol – 724 mL

x mol – 1000 mL

$x = \frac{1.153 \times 1000}{724}= 1.59 \;mol/L ≈1.6 \;M$

Answer: 1.6 M