For a reaction to be spontaneous at all temperatures :

• ΔG and ΔH should be negative

• ΔG and ΔH should be positive

• ΔG =ΔS = 0

• ΔH< ΔG

For a reversible reaction:

$\mathrm{X}\left(\mathrm{g}\right) + 3\mathrm{Y} \left(\mathrm{g}\right) \rightleftharpoons 2\mathrm{Z} \left(\mathrm{g}\right) ; ∆\mathrm{H} = -40\mathrm{kJ}$, the standard entropies of X, Y and Z are 60, 40 and 50 JK^-1 mol^-1 respectively. The temperature at which the above reaction attains equilibrium is about :

• 400 K

• 500 K

• 273 K

• 373 K

Among the alkali metals cesium is the most reactive because :

• its incomplete shell is nearest to the nucleus

• it has a single electron in the valence shell

• it is the heaviest alkali metal

• the outermost electron is more loosely bound than the outer most electron of the other alkali metals

During the fusion of an organic compound with sodium metal, nitrogen of the compound is converted into :

• NaNO₂

• NaNH₂

• NaCN

• NaNC

Which cycloalkane has the lowest heat of combustion per CH₂ group?

• Cyclopropane

• Cyclobutane

• Cyclopentane

• Cyclohexane

16.

Inductive effect involves:

• displacement of σ-electrons

• delocalisation of π-electrons

• delocalisation of σ-electrons

• displacement of π-electrons

Which of the following solutions will exhibit highest boiling point?

• 0.01M Na₂SO₄ (aq)

• 0.1M KNO₃ (aq)

• 0.015 M urea(aq)

• 0.015 M glucose(aq)

Which of the following is not an ore of magnesium?

• Carnallite

• Dolomite

• Calamine

• Sea water

The atomic number of Ni and Cu are 28 and 29 respectively. The electronic configuration. 1s²2s²2p⁶3s²3p⁶3d¹⁰ represents.

• Cu⁺

• Cu²⁺

• Ni²⁺

• Ni

In the following, the element with the highest ionisation energy is :

• [Ne]3s²3p¹

• [Ne]3s² 3p³

• [Ne]3s² 3p²

• [Ne]3s² 3p⁴