chemestry
posted by anomimo on .
1.0000 g of hydrate of stannic chloride with unknown formula is heated to 100C (celsius) for 30 minutes. The remaining anhydrous salt weighted 0.7836g. What is the formula of this hydrate?
thanks

Stannic chloride is SnCl4 and the hydrate is SnCl4.xH2O
SnCl4.xH2O ==> SnCl4 + xH2O
1.000...........0.7836..0.2164
mols = grams/molar mass
Convert g to moles.
moles SnCl4 = 0.7836/molar mass
moles H2O = 0.2164/molar mass.
Then find the ratio of the two elements to each other with SnCl4 being 1.00. The easy to do that is to divide moles SnCl4 from above by itself (thereby assuring you get 1.00 for that value) then divide the moles H2O by the same number. Round the final value to a whole number and that will give you x. Post your work if you get stuck. 
it shouldnt be the ratio of
SnCl4/ H2o....
and the ratio of
H2o/ H20 =1
?? 
C'mon. My directions aren't that bad.
moles SnCl4 = 0.7836/260.5 = 0.003008
moles H2O = 0.2164/18.015 = 0.01201
0.003008/0.003008 = 1.000
0.01201/0.003008 = 3.992 which rounds to 4.0 and the formula is
SnCl4.4H2O
Note: I consider this a freebie for you in which I have worked the entire problem for you. Your response to my instructions makes no sense at all and COULD be construed as being done on purpose to get an entire problem worked for you from scratch. Sorry if that sounds harsh and especially sorry if that isn't true; however, I will not be so accommodating in the future.