Chemistry paper 3 help please!!

[WW66F1980]

I've come across a question on the May/June 2009 IGCSE Chemistry Paper 3 past paper exam.

It's question 5(b) (first variant) of this paper: http://www.xtremepapers.me/CIE/Cambridg ... 9_qp_3.pdf

I've checked the mark scheme and all is says is T3(PO4)2 but I've no idea why that's the answer. I know it's something to do with mole ratio but really can't work it out!

Please help someone.

 

[sagittarius94]

seriously i had the same question,i know no one who can help me with this.......i just cant figure it out.i dont know how can we deduce the formula from that information!!!!

 

[WW66F1980]

It's impossible! I just hope to God that there isn't a question like this in the exam.

 

[sagittarius94]

yeah me too.So did u give bio too? how did it go? and todayz chem p6?