[nikivds]

Hi,

I'm at Sydney Uni and I have a few questions from my practice mid-semester exam. One of them involves stoichiometry with hydrates. I read a previous topic on this but I still don't understand it. I know its suppossed to be simple. Here's what I have, i was wondering if it looks right?

Q? How much CrCl3.6H20 is needed to make up 100ml of a 0.020molar solution?

A: moles = 0.02*100/1000 = 0.002 moles
    weight = 0.002*266.35 = 0.5327g

seems a bit low and I didn't accouont for the h20's because I don't know how...
thanks guys!

[AWK]

OK

[sjb]

How would you calculate the mass required if the formula you were given were "H₆CrCl₃(OH)₆"?

Essentially if you want a mass of compound to make up a solution this is the same compound.