Question

A sample of compound weighing 83.5 g contains 33.4 g of sulfur. The rest is of oxygen. What is the empirical formula?

Answer 1

Question:

A sample of compound weighing 83.5 g contains 33.4 g of sulfur. The rest is of oxygen. What is the empirical formula?

Solution:

Empirical formula: $\mathrm{S_xO_y}$

There x:y - the simplest positive integer ratio of atoms present in a compound.

And x:y=n(S):n(O),

n(S)=m(S)/M(S)=33.4/32=1.04mol

m(O)=m(sample)-m(S)=83.5-33.4=50.1g

n(O)=m(O)/M(O)=50.1/16=3.13mol

n(S):n(O)=1.04:3.13=(simplify ratio to integers)=1:3;

so our empirical formula of compound is $\mathrm{SO_3}$

Answer: $\mathrm{SO_3}$