22487.Identify the reaction that does not take place in a blast furnace.
CaCO3 → CaO + CO2
CaO + SiO2 → CaSiO2 → CaSiO3
2Fe2O3 + 3C → 4Fe + 3CO2
CO2 +C → 2CO
22488.Formation of coloured solution is possible when metal ion in the compound contains
paired electrons
unpaired electrons
lone pair of electrons
none of these
22489.Iron exhibits +2 and + 3 oxidation states. Which of the following statements about iron is incorrect?
Ferrous oxide is more basic in nature than the ferric oxide
Ferrous compounds are relatively more ionic than the corresponding ferric compounds
Ferrous compounds are less volatile than the corresponding ferric compounds
Ferrous compounds are more easily hydrolyzed than the corresponding ferric compounds.
22490.What is the correct order of spin only magnetic moment (in BM) of Mn2+, Cr2+ and V2+?
Mn2+ > V2+ > Cr2+
V2+ > Cr2+ > Mn2+
Mn2+ > Cr2+ > V2+
Cr2+ > V2+ > Mn2+
22491.In context of the lanthanoids, which of the following statements is not correct?
Availability of 4 f electrons results in the formation of compounds in +4 state for all the members of the series
There is a gradual decrease in the radii of the members with increasing atomic number in the series
All the members exhibit +3 oxidation state
Because of similar properties the separation of lanthanoids is not easy
22494.Larger number of oxidation states are exhibited by the actinoids than those by the lanthanoids, the main reason being
4f orbitals more diffused than the 5f orbitals
lesser energy difference between 5f and 6d than between 4f and 5d orbitals
more energy difference between 5f and 6d than between 4f and 5d orbitals
more reactive nature of the actinoids than the lanthanoids
22495.Which one of the following molecules is expected to exhibit diamagnetic behaviour?
C2
N2
O2
S2
22496.What would happen when a solution of potassium chromate is treated with an excess of dilute nitric acid?
Cr3+ and Cr2O2–
7
7
Cr2O2–
7 and H2O are formed
7 and H2O are formed
Cr2O2–
4 is reduced to +7 state of Cr
4 is reduced to +7 state of Cr
Cr2O2–
4 is reduced to +3 state of Cr
4 is reduced to +3 state of Cr
22497.The ground state electronic configuration of CO molecule is
1σ22σ21π43σ2
1σ22σ23σ21π22π2
1σ22σ21π23σ22π2
1σ21π42σ23σ2
22498.Of the following outer electronic configurations of atoms, the highest oxidation stateis achieved by which one of them?
(n – 1) d8 ns2
(n – 1) d5 ns1
(n – 1) d3 ns2
(n – 1) d5 ns2
22500.Mercury is a liquid metal because
it has a completely filled s–orbital
it has a small atomic size
it has a completely filled d–orbital that prevents d–d overlapping of orbitals
it has a completely filled d–orbital that causes d–d overlapping
22501.The actinoids exhibits more number of oxidation states in general than the lanthanoids. This is because
the 5f orbitals are more buried than the 4f orbitals
there is a similarity between 4f and 5f orbitals in their angular part of the wave function
the actinoids are more reactive than the lanthanoids
the 5f orbitals extend further from the nucleus than the 4f orbitals
22502.The bonds present in the structure of dichromate ion are
four equivalent Cr – O bonds only
six equivalent Cr – O bonds and one O – O bond
six equivalent Cr – O bonds and one Cr – Cr bond
six equivalent Cr – O bonds and one Cr – O – Cr bond
22503.Which of the following lanthanoid ions is diamagnetic? (At. nos. Ce = 58, Sm = 62, Eu = 63, Yb = 70)
Ce2+
Sm2+
Eu2+
Yb2+
22504.The methods chiefly used for the extraction of lead and tin from their ores are respectively
self reduction and carbon reduction
self reduction and electrolytic reduction
carbon reduction and self reduction
cyanide process and carbon reduction