Hello, me again. I have come across another question which I really can't seem to be able to get my head around. If you could help, I would be extremely happy. (not kidding, since im very frustrated at the moment).
A student was asked to find the relative atmic mass of an element X. Crystals of the choride of X were known to have the formula XCl2
The student dissolved 2.03g of the crystals in water, and then added an axcess of silver nitrate solution to the solution formed. A white precipitate of silver chloride was formed, which was filtered, dried and weighed. 2.87g were formed.
-> AgCl (s)
(a) the number of moles of silver chloride formed
(b) the number of moles of X chloride in the solution (you may assume that all the chlorine in X chloride is in solution as Cl-(aq)
(c) the mass of 1 mole of XCl2
(d) the relative atmic mass of X.
I have already calculated (a), which was quite easy:
2.87/143.5 = 0.02mol
Yet i have not a clue how to start on (b)