31. Which transition metal forms a yellow complex with chlorine?

a) Iron
b) Copper
c) Chromium
d) Manganese
Answer: c) Chromium

32. The oxidation state of iron in ferrous sulfate (FeSO4\text{FeSO}_4FeSO4​) is:

a) +2
b) +3
c) +4
d) +6
Answer: a) +2

33. The transition metal that exhibits a blue color in its aqueous solution is:

a) Copper
b) Iron
c) Zinc
d) Manganese
Answer: a) Copper

34. Which transition metal is used in the synthesis of methanol from carbon monoxide and hydrogen?

a) Iron
b) Cobalt
c) Nickel
d) Platinum
Answer: a) Iron

35. The common oxidation state of cobalt in its complexes is:

a) +2
b) +3
c) +4
d) +6
Answer: a) +2

36. The transition metal that has the electron configuration [Ar] 4s^2 3d^7 is:

a) Nickel
b) Iron
c) Cobalt
d) Copper
Answer: c) Cobalt

37. The complex ion [CuCl4]2−[\text{CuCl}_4]^{2-}[CuCl4​]2− has a geometry that is:

a) Octahedral
b) Square planar
c) Tetrahedral
d) Linear
Answer: c) Tetrahedral

38. Which of the following is a property of transition metals?

a) High atomic radii
b) High ionization energy
c) Low melting points
d) Low density
Answer: b) High ionization energy

39. The term “coordination complex” refers to:

a) A single metal ion
b) A metal ion surrounded by ligands
c) A metal atom without any ligands
d) An ionic compound of a metal
Answer: b) A metal ion surrounded by ligands

40. The transition metal used in the synthesis of synthetic diamonds is:

a) Iron
b) Nickel
c) Platinum
d) Cobalt
Answer: d) Cobalt