I searched for it and couldn't find it...well anyways I have some mroe questions I've been working on, and failing miserably.

1. 4.34-g geological sample, containing the mineral Boulangerite (Pb5Sb4S11) as the only lead-bearing compound, is subjected to chemical treatment in which the lead is quantitatively recovered as solid PbCl2. The mass of PbCl2 obtained is 2.18 g.
What was the percentage (by mass) of Pb5Sb4S11 in the sample?

So I found the mass % of Pb in PbCl2 (74.5 %) x 2.18 g = 1.62 g

And I found the mass % of Pb in Pb5Sb4S11 (55.22 %)

..but I'm not sure where to go from there...
Quote by pataldo
"Didn't there used to be"? i'm glad you're not working on English.
shut up.

TS, there's a Science and Maths help thread.
Go to the Forbidden threads sticky to get the link.
Quote by Jackal58
I release my inner liberal every morning when I take a shit.
Quote by SK8RDUDE411
I wont be like those jerks who dedicate their beliefs to logic and reaosn.