can anyone help with molality?

Question

What is the molality of a solution consisting of 3.03 mL of carbon tetrachloride (CCl4, d = 1.59 g/mL) in 83.1 mL of methylene chloride (CH2Cl2, d = 1.33 g/mL)?

Answer 1

molality is the number of moles of solute per 1 kg of solvent.
Your solute is CCl4
you have moles CCl4= mass/MW
and because d=mass/V =>mass =d*V
moles CCl4 = d*V/MW =1.59* 3.03/154=0.03128

You have m=d*V= 1.33*83.1=110.523 gr CH2Cl2 (solvent)

so you have 0.03128 mole solute in 110.523 gr solvent
x mole solute in 1000 gr solvent

Thus x=0.03128 *1000/110.523=0.283

Answer 2

use the formula Y=MX+B
or just go to limewire