What is the characteristic smell of hydrogen sulphide gas?

Sample 'A' contains iron filings and sulphur powder, Sample 'B' is iron sulphide. Sample 'A' and 'B' are taken on a watch glass and a bar magnet is rolled over both.

You will observe that: 

Give the characteristic test for the following gas.

 ${\mathrm{H}}_2$

Describe the various steps involved in the separation of iodine, iron filings and salt from a mixture.

Give reason for the following statement:

Magnetic separation cannot be used to separate a mixture of copper and sulphur.