An element occupies group No.16 and period number 2. This element on passing through silent electric discharge forms (A). (A) also reacts with lead sulphide and forms (B). (A) also reacts with `BaO_(2)` and forms (C). It reacts with `H_(2)O_(2)` and forms (D). Identify the element (A), (B), (C) and (D).

F_(2) reacts with H_(2)S and forms

Cl_2 reacts with water and forms

CaC_(2) react with H_(2)O to form which gas

Aluminium react with Na_(2)CO_(3) to form

An element occupies group no.13 and period number 2 is an representative element of that group reacts with carbondioxide and forms an oxide (A). (A) reacts with CuSO_(4) give blue beads (B). Identify the element compound (A) and (B). Write the reaction.

An element occupies group No.14 and period number 2 exists in different allotropic forms. One form of this element has lubricating property (A). Another form is the hardest substance (B). New allotrope of this element is named as Buckyball' (C) and it is superconducting. Identify the element, (A) (B) and (C).

BF_(3) reacts with LiH and forms a compound A. The compound A reacts with water to give the compound B. A reacts with ammonia at 390 K and form C. Identify (A), (B) and (C).

When Cl_2 reacts with Fe (or) Cu it does not form