simple molality question

[noles]

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If 10g NaOH is dissolved in 500g of water, what is the molality of the solution?

Would the answer be .5m or 1m?

10g NaOH = .25 mol NaOH

So would it be .25/.5 = .5m

or

Since we're talking about a solution do we take into account the ions that dissociate?

NaOH -> Na+ OH-

(.25 mol Na + .25 mol OH)/.5 = 1m

???

thanks in advance

 

[MTD52]

I believe NaOH is the solute and that's all you need to know for molality, since it's just (moles solute/kg solvent)

You would be right with the first answer I think.

 

[mx41]

Dissociation has nothing to do with molality. It's simply (moles solute)/kg solvent

First answer is correct.

 

[noles]

thought so.. my kaplan teacher is wrong

thanks

 

[MTD52]

thought so.. my kaplan teacher is wrong

thanks

That's promising lol

 

[dentrilla]

yah my kaplan teacher had some issues as well... only thing kaplans good for is they're BB

 

[ethanyoo726]

Molality: moles of solute / kg of solvent...

your first answer is correct.