Question

A sample of vinegar containing 4,2 g of acetic acid C2H4O2 per 100ml has the concentration of this acid in mol / l equal to

Answer 1

Molar mass :

C2 H4 O2 = 12. 2 + 1.4 + 16.2 => 60.0 g / mol

Calculation of the quantity in mols of the solute:

N = m / mm

N = 4.2 / 60.0

N = 0.07 mols

Volume in liters of solution:

100 mL / 1000 => 0.1 L

Lastly :

M = n / V

M = 0.07 / 0.1

M = 0.7 mol / L