11) What is the nature of Zn (OH) ₂?

a) Amphoteric.
b) Basic
c) Acidic
d) Neutral

ANSWER : Amphoteric.

12) Which of the following will show maximum magnetic moment?

a) 3d⁹
b) 3d⁵
c) 3d⁷
d) 3d⁸

ANSWER : 3d⁵

13) Due to which property Zr and Hf shows similar atomic and ionic size?

a) Diagonal relationship
b) They have similar chemical properties.
c) Lanthanide contraction.
d) They are in the same group.

ANSWER : Lanthanide contraction.

14) Which among the following is a Zeigler – Natta?

a) Pt
b) Pt/Rh
c) TiCl₄/Al(C₂H₅)₃
d) Pt/PtO catalyst

ANSWER : TiCl₄/Al(C₂H₅)₃

15) Similarity between Nb and Ta is because they:

a) Are transition metals.
b) Have the same mineral source.
c) Have almost same ionic and covalent radii.
d) Belong to same group of periodic table.

ANSWER : Have almost same ionic and covalent radii.

16) Cd²⁺ is isoelectronic with:

a) Zn²⁺
b) Pb²⁺
c) Cu²⁺
d) Ag+

ANSWER : Ag+

17) Which among the following is also known as Adam’s catalyst used for reduction?

a) Pt/PtO
b) Pb
c) Pt
d) Pt/Rh

ANSWER : Pt/PtO

18) Which catalyst is used for making Cl₂ from HCl in Deacon’s process?

a) SiCl₂
b) CuCl₂
c) Both a and b
d) None of these.

ANSWER : CuCl₂

19) The process of reduction of ores with carbon is known as:

a) Thermite process
b) Roasting
c) Smelting
d) Zone refining

ANSWER : Smelting

20) The most widely used commercial chemical as a paint pigment is:

a) SiO₂
b) MgO
c) Al₂O₃
d) TiO₂

ANSWER : TiO₂ 

Part 1   Part 2   Part 3   Part 4   Part 5