Which of the following is not an example of redox reaction?

1. $\mathrm{CuO}+{\mathrm{H}}_2\to \mathrm{Cu}+{\mathrm{H}}_2\mathrm{O}$

2. ${\mathrm{Fe}}_2{\mathrm{O}}_3+3\mathrm{CO}\to 2\mathrm{Fe}+3{\mathrm{CO}}_2$

3. $2\mathrm{K}+{\mathrm{F}}_2\to 2\mathrm{KF}$

4. ${\mathrm{BaCl}}_2+{\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{BaSO}}_4+2\mathrm{HCl}$

Match Column I with Column II for the oxidation states of the central atoms.

Codes:

Match the items in Column I with relevant items in Column II.

Codes:

Which of the following statements are not true about the following decomposition reaction?

$2{\mathrm{KClO}}_3\to 2\mathrm{KCl}+3{\mathrm{O}}_2$

The correct choice from the above is:

1. a, b and d

2. b, c and d

3. b, d and a

4. None of the above

 Atom(s) with outer most electronic configuration among the following that can show variable oxidation is

(a) 3s¹

(b) 3d³4s²

(c) 3d²4s²

(d) 3s²3p³

1. (a, b, c)

2. (b, c, d)

3. (a, b, d)

4. (a, c, d)