- #1

soggybread

- 20

- 0

**Having a massive brain fart... SIMPLE "molarity -> molality" conversion...**

This isn't even a homework question per se, I'm just trying to understand how the question converted the molarity to the molality value, via the density given. I just got a different value of molality when trying to solve for it manually... and am pretty sure I did something stupid.

## Homework Statement

If the osmotic pressure of a

**6.02×10**was found to be 4.05 atm at 20°C.

^{-2}M aqueous solution of Ca(NO_{3})_{2}**Note that the corresponding molality would be 6.10×10**, given that the density of the solution is 0.997 g/cm

^{-2}m^{3}...

## Homework Equations

None.

## The Attempt at a Solution

Okay... so the question tells me it has a molality of 6.10×10

^{-2}m,

So if I want to solve for that myself, I would start off with the given molarity, right? So it would be

**6.02×10**then multiply it by the density of solution, 0.997g/cm

^{-2}M^{3}, or in other words,

**0.997kg/1L**... and then we're done, right?

So:

**6.02×10**multiply

^{-2}mol/L**1L/0.997kg**=

**6.04x10**

^{-2}... but the question tells me it's

**6.10×10**... and I have no idea why I'm not getting that value.

^{-2}mI don't know what's going wrong here... I'm sure I am missing something dead simple...