What is the molarity of: 40.0 grams of sodium hydroxide in 1.50L of solution? What is the molarity of: 4.10 grams of magnesium chloride in 300.mL of solution?

1 Answer
Apr 3, 2018

0.667 M concentration of 40.0 g of #Na(OH)_2# in 1.5 L of solution.
0.14 M concentration of 4.10 g of #MgCl_2# in 300 mL of solution.

Explanation:

GFM of #Na(OH)_2# = 40 g/mol.
Moles of sodium hydroxide in 40.0 grams = 1 mol.
Molarity = number of moles / liters of solution = 1 mol / 1.5 L = 0.667 M.

GFM of #MgCl_2# = 95 g/mol
Moles of magnesium chloride in 4.10 grams = grams of substance / gram formula mass = 4.10 g / 95 g/mol = 0.04316 mol
Molarity = number of moles / liters of solution = 0.04316 mol / 0.3 L = 0.14 M