Question

Mohan prepared a solution having mass percentage 20% and density 1.2 g/ml. Calculate molarity,molality and mole fraction..



Please answer this
I will mark as brainlest!!!!

Answer 1

Mohan prepared a solution having mass percentage 20% .

density , d = 1.2 g/ml

molarity = mass percentage × d × 10/molecular weight of solute

you didn't mention about solute ,

Let us consider that molecular weight of solute is M

then, molarity = 20 × 1.2 × 10/M

= 240/M mol/Litre

mass percentage = 20%

it means, 20g of solute present in 100g of solution.

so, mass of solvent = 100g - 20 = 80gm

now, molality = number of mole of solute/mass of solvent in kg

= (20/M) × 1000/80

= 250/M mol/kg

mole fraction of solute = mole of solute/(mole of solute + mole of solvent)

= (20/M)/(20/M + 80/18)

[ as molar mass of water is 18g/mol]

just you have to put value of M( molar mass of solute ) you will get all answers.