# What mass of potassium chloride should be dissolved in a 500*mL volume of aqueous solution to give a concentration of 1*mol*L^-1?

Approx. $37 \cdot g$.....
$37 \cdot g$ of salt could be dissolved in a $500 \cdot m L$ volume of water to give a $1 \cdot m o l \cdot {L}^{-} 1$ solution with respect to $K C l$. Its purity depends on the purity of the salt you use to make it.