Given below are certain cations. Using inorganic qualitative analysis, arrange them in increasing group number from 0 to $$\mathrm{VI}$$.

A. $$\mathrm{Al}^{3+}$$

B. $$\mathrm{Cu}^{2+}$$

C. $$\mathrm{Ba}^{2+}$$

D. $$\mathrm{Co}^{2+}$$

E. $$\mathrm{Mg}^{2+}$$

Choose the correct answer from the options given below.

Match the List - I with List - II

Choose the correct answer from the options given below :

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Helium is used to dilute oxygen in diving apparatus.

Reason R : Helium has high solubility in O$$_2$$.

In the light of the above statements, choose the correct answer from the options given below:

Match List I with List II:

Choose the correct answer from the options given below: