Question

An aqueous solution of H202 is 34.02, and 30.0% by mass.. 1.11 g/mL Whats is the molaity of h202

R= 8.314? .. K-moj= 0.8206

Answer 1

we have given mass of aqueous solution of H2O2 = 34.02 g

{note : 34.02 g is mass solution than this calculation is correct if not than assume 100 g (for calculation simple), of solution mass and follow same methode and answer will be same }

and H2O2 is 30 % by mass so, mass of H2O2 = (34.02 g) 30/100 = 10.206 g

mass of H2O = (34.02 - 10.206 ) g = 23.814 g

now, find moles of H2O2 = mass / molar mass = (10.206 g / 34.02 g/mol) = 0.3 moles

molality = moles of solute / mass of solvent in Kg

molality = (0.3 moles / 0.023814 kg ) = 12.6 m H2O2