Posted by Anonymous on .
A metal, M, of atomic mass 91 amu reacts with fluorine to form a salt that can be represented as MFx. In order to determine x and therefore the formula of the salt, a boiling point elevation experiment is performed. A 9.05g sample of the salt is dissolved in 100.0 g of water and the boiling point of the solution is found to be 374.54 K. Find the formula of the salt. Assume complete dissociation of the salt in solution.
Is the answer not MF_3??

Chemistry 1046 
bobpursley,
assume it is MF3. then
bpe=.52*4*9.05/(.1*(91+3*19))
bpe=18.8/(14.8)=1.2 check that.
Is that equivalent to a new bp of 374.54K? 
Chemistry 1046 
Anonymous,
It is not... So where do I go from here?

Chemistry 1046 
DrBob222,
You're right. It isn't MF3.
Do it this way.
delta T = i*Kb*m
If you let MFx ionize into M + xF, then
molar mass is 91+19x and
m = 90.5g/(91+19x)
Substitute delta T, for i substitute x+1, then Kb and m. Solve for x. 
Chemistry 1046 
ANA,
the answer should be ZrF4

Chemistry 1046 
someone,
ZrF4 is wrong.

Chemistry 1046 
someone,
This is an OLD question but I'm having trouble on it... *sigh*