Question

Calculate the molarity of the hydrochloric acid.

Answer 1

Hydrochloric acid is a saturated aqueous solution of hydrogen chloride, HCl.

The solubility of HCl in water is 72.47g per 100g of water. As a percentage, this will be 72.47/(100+72.47)=0.42 or 42%.

The density of the HCl solution with a concentration of 42% is 1.208g/cm3 according to the reference data.

The molarity is calculated by the formula: c_HCl=n_HCl/V_solution.

n_HCl = m_HCl/M_HCl=72.47g/36.5 g*mol^-1=1.985mol.

V_solution=m_solution/d_solution=(100 g+72.47 g)/(1.208 g/cm³)=142.77cm³=0.14277 l.

c_HCl=1.985 mol/0.14277 l=13.9mol/l.

Answer: the molarity of hydrochloric acid is 13.9mol/l.