Question

A sample having a mass of 0.924 g was decomposed into its components and found to have 0.389 g of carbon, 0.059 g of H and 0.476 g of O. Find the percentage composition of this substance. 3.13. What is the empirical formula of a compound consisting of 7.8 g of potassium, 7.1 g of chlorine and 9.6 g of oxygen?
​

Answer 1

Answer:

Number of gm of oxygen in 32.2 g Na

2

SO

4

.10H

2

O is No. of oxygen atoms in one molecule =4+10=14

Thus moles of oxygen in n moles of compound=14n

Molar mass of Na

2

SO

4

.10H

2

O=46+32+64+180=322g/mol

Thus

32.2g=

322

32.2

=0.1 mols

Thus moles of O=0.1×14=1.4

So weight is

16×1.4=22.4g