Question

Which aqueous solution has a molarity of $1.0M$?

• A. $73$ grams of $HCl$ dissolved to make $2.0$ liters of solution
• B. $360$ grams of $C_6{H}_{12}{O}_6$ dissolved to make $1.5$ liters of solution
• C. $94$ grams of $K_{2}O$ dissolved to make $0.75$ liters of solution
• D. $24$ grams of $LiOH$ dissolved to make $1.25$ liters of solution
• E. $40$ grams of $HF$ dissolved to make $2.50$ liters of solution

Answer 1

The correct option is A $73$ grams of $HCl$ dissolved to make $2.0$ liters of solution

The following aqueous solution has a molarity of 1.0 M
73 grams of $HCl$ dissolved to make 2.0 litres of solution
The molar mass of HCl is 36.5 g/mol. The number of moles of $HCl$ is the ratio of its mass to molar mass. The number of moles of HCl $=\frac{73g}{36.5g/mol}=2moles.$
The molarity of HCl solution is the ratio of number of moles of $HCl$ to volume of solution (in L).
Molarity $=\frac{2.0mol}{2.0L}=1M$