X [Oxygen, Sulphur, Selenium] and Y [Neon, Argon, Xenon] are two sets of elements. Using these elements complete the following.

(a) Set …………… is known as noble gases.

(b) In set X …………… has the highest electronegativity.

(c) The …………… set contains the non-metals.

(a) For each of the substances given below, what is the role played in the preparation of NH₃ (ammonia)

(a) CaO

(b) Mo

The following questions are asked with respect to the electrolytic process in the extraction of aluminium.

(a) Identify the components of the electrolyte other than pure alumina.

(b) Give the role played by these components.

Rajat mixed a white coloured compound A with water. The compound A reacted vigorously with water to produce a compound B and large amount of heat. He used the compound B to white wash the walls.

After 3 days of whitewash, the walls became shiny

(a) Name the compound A

(b) Why the walls appear shiny ? Write the reactions involved.

(c) State the type of reaction occurred here.