How many grams of potassium chloride are required to make 250 ml of a 0.75 m kcl solution?

The solution would need 13.9 g of KCl

Explanation:

0.75 m, means molal concentration

0.75 moles in 1 kg of solvent.

Let's think as an aqueous solution.

250 mL = 250 g, cause water density (1g/mL)

1000 g have 0.75 moles of solute

250 g will have (0.75. 250) / 1000 = 0.1875 moles of KCl

Let's convert that moles in mass (mol. molar mass)

0.1875 m. 74.55 g/m = 13.9 g