JEE Advanced 2011 · Paper 2

Oxidation states of the metal in the minerals haematite and magnetite, respectively, are

1. AII, III in haematite and III in magnetite
2. BII, III in haematite and II in magnetite
3. CII in haematite and II, III in magnetite
4. DIII in haematite and II, III in magnetite

Among the following complexes (K–P), K₃[Fe(CN)₆] (K), [Co(NH₃)₆]Cl₃ (L), Na₃[Co(oxalate)₃] (M), [Ni(H₂O)₆]Cl₂ (N), K₂[Pt(CN)₄] (O) and [Zn(H₂O)₆](NO₃)₂ (P) the diamagnetic complexes are

1. AK, L, M, N
2. BK, M, O, P
3. CL, M, O, P
4. DL, M, N, O

Passing H₂S gas into a mixture of Mn²⁺, Ni²⁺, Cu²⁺ and Hg²⁺ ions in an acidified aqueous solution precipitates

1. ACuS and HgS
2. BMnS and CuS
3. CMnS and NiS
4. DNiS and HgS

Consider the following cell reaction: 2Fe(s) + O₂(g) + 4H⁺(aq) → 2Fe²⁺(aq) + 2H₂O(l) E° = 1.67 V At [Fe²⁺] = 10⁻³ M, P(O₂) = 0.1 atm and pH = 3, the cell potential at 25 °C is

1. A1.47 V
2. B1.77 V
3. C1.87 V
4. D1.57 V

The freezing point (in °C) of a solution containing 0.1 g of K₃[Fe(CN)₆] (Mol. Wt. 329) in 100 g of water (Kf = 1.86 K kg mol⁻¹) is

1. A−2.3 × 10⁻²
2. B−5.7 × 10⁻²
3. C−5.7 × 10⁻³
4. D−1.2 × 10⁻²

Reduction of the metal centre in aqueous permanganate ion involves

1. A3 electrons in neutral medium
2. B5 electrons in neutral medium
3. C3 electrons in alkaline medium
4. D5 electrons in acidic medium

The equilibrium 2 Cuᴵ ⇌ Cu⁰ + Cuᴵᴵ in aqueous medium at 25 °C shifts towards the left in the presence of

1. ANO₃⁻
2. BCl⁻
3. CSCN⁻
4. DCN⁻

For the first order reaction 2N₂O₅(g) → 4NO₂(g) + O₂(g)

1. Athe concentration of the reactant decreases exponentially with time.
2. Bthe half-life of the reaction decreases with increasing temperature.
3. Cthe half-life of the reaction depends on the initial concentration of the reactant.
4. Dthe reaction proceeds to 99.6 % completion in eight half-life duration.