Question

820 g Li2SO4 is dissolved into 2500 mL of solution. What is the molar concentration?

Answer 1

Molarity is defined as the moles of solute per liter of solution.
`M=(n)/(V)`. Where M is molarity, n is the number of moles and V is the volume. First we must find the molar mass of
`Li_2SO_4` which is 109.98 g/mol

`Li_2SO_4= 2 * Li_(Ar) + S_(Ar) + 4 * O_(Ar)\\= (2 * 6.941 + 32.1 + 4 * 16.0) = 109.98 g/mol`

`820\ g\ Li_2SO_4 * (mol)/(109.98\ g)= 7.46\ mol\ Li_2SO4`

Then we find the molarity using above equation

`M= (n)/(V) = (7.46 mol)/(2500ml) *(1000ml)/(L) = 2.98\ M`