A sample of dichloroacetic acid (MW = 128.94 g/mol) weighing 6.447 g is dissolved in water in a 500 mL volumetric flask. The resulting formality of the solution is?

A sample of dichloroacetic acid (MW = 128.94 g/mol) weighing 6.447 g is dissolved in water in a 500 mL volumetric flask. The resulting formality of the solution is?

Explanation

To calculate formality, we need to know the number of moles of dichloromethanic acid and the volume of the solution in liters.

Number of moles = mass / molecular weight

= 6.447 g / 128.94 g/mol

≈ 0.05 mol

Formality = number of moles / volume (in liters)

= 0.05 mol / 0.5 L

= 0.1 F