Where am I messing up??

Question

amtran_bus · Answer

From the solubility data given, calculate the solubility products for the 					following compounds: 
			(a) SrF2, 7.3 x 10-2 g/L 	
			(b) Ag3PO4, 6.7 x 10-3 g/L

amtran_bus · Answer

For part a, cant you say7.3x10^-2 =4s^3??

amtran_bus · Answer

@aaronq

aaronq · Answer

you converted to the masses to moles?

amtran_bus · Answer

By dividing by the molar mass?

aaronq · Answer

yeah

amtran_bus · Answer

7.3x10^-2/125.62=.000581
Now divide by 4 and take cubed root of ans?

aaronq · Answer

no, i think they're asking you for the solubility product constant.

so Ksp=$4(0.000581)^3$

amtran_bus · Answer

OHH! So solubility =s and molar solubility =Ksp?

aaronq · Answer

yeaah

amtran_bus · Answer

Thanks! Never ran into a problem like that before.

aaronq · Answer

no problem! i think thats what they're asking for, you should double check though

amtran_bus · Answer

Ok. I know usually you make the ICE table to determine the factor (like 4s^3).

aaronq · Answer

yeah, you would, but you can always assume it's that when you have a $XY_2$ compound