molarity and molality hen density is given?

Question

The density of a bottle of concentrated HCl has a density of 1.2g/ml and contains 36% of HCl. what is the molarity and molality of HCl in this solution?

Answer 1

molarity= (10*density of hcl*% of hcl)/ mol wt of hcl

M=(10*36*1.2)/37.5
=11.52

N=(%*10*density)/gram equivalent mass

Answer 2

Molarity is moles/liter of solution and molality is moles per kg of solution. So start with 1 liter of solution, which weights 1200 gm of which 36 pct is HCl, or 432 grams. Divide 432 grams by 37.5 g/g-mole HCl (I think!!). That will give you the molarity. For molality, divide 360 grams by 37.5 g/g-mole for the answer. BTW, 12M is the "standard" for conc HCl solution. Above that, you get into the weird world of having a HCl solution of water.

Answer 3

Your question is worded wrong, don't repeat "molarity and molarity." But I understand it anyway. Here's one way to calculate molarity:

M = mol / L, where mol represents number of moles and L is
liters, obviously.

1mole of HCl = 36.6g (add the atomic masses of H and Cl)

I can almost calculate it. However, the fact that only 36% of the solution is HCl make it more complicated because I don't know at which propotions the other substances are present. I fail :(