Question #25b38

1 Answer
May 25, 2016

Al2(SiO3)3

Explanation:

We can proceed by calculating masses of elements X,Y and Z present in the molar mass of the compound X2(YZ3)3
using the given percentage composition of the compound.
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So mass of X present in one mole of the compound is 282.23×19.12%g=53.96g
Since according to the formula of the comound its molecule contains 2 atoms of X ,
the molar mass of X=53.962=26.98gmol
Now from periodic table it is found that X is nothing but Al.

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Similarly mass of Y in molar mass of the compound is
282.23×29.86%=84.27g.
As the molecule contains 3 atoms of Y,
molar mass of Y=84.273=28.09gmol
According to periodic table it should be Si.

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Now finally 9 atoms of y are present in one molecule of the comound and its mass in one mole of the compound is
282.23×51.02%144g
Hence molar mass of Z=1449=16gmol
Consulting periodic table we can say the element Z is Oxygen O

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So the compound will have formula Al2(SiO3)3 which is Aluminium silicate