The most probable radius (in pm) for finding the electron in He⁺ is

• 0.0

• 52.9

• 26.5

• 105.8

For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, $∆$U and w corresponds to

• $∆$U < 0, w = 0

• $∆$U < 0, w < 0

• $∆$U > 0, w = 0

• $∆$U > 0, w > 0

For reaction, 2NOCl _(g) $\rightleftharpoons$2NO _(g) + Cl_2 (g), K_c at 427°C is 3 × 10^-6 L mol^-1. The value of K_p is nearly

• 7.50 × 10^-5

• 2.50 × 10^-5

• 2.50 × 10^-4

• 1.75 × 10^-4

For the chemical equilibrium,

CaCO_3(s) $\rightleftharpoons$CaO_(s) + CO_2(g)

$∆{\mathrm{H}}_{\mathrm{r}}^{°}$ can be determined from which one of the following plots?

Assertion : Potassium ferrocyanide is diamagnetic whereas potassium ferricyanide is paramagnetic.

Reason : Crystal field splitting in ferrocyanide ion is greater than that of ferricyanide ion.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

16.

Assertion : SeCl₄ does not have a tetrahedral structure.

Reason : Se in SeCl₄ has two lone pairs.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : First ionization energy for nitrogen is lower than oxygen.

Reason : Across a period effective nuclear charge decreases.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : B₂ molecule is diamagnetic.

Reason : The highest occupied molecular orbital is of σ type.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

In the balanced chemical reaction
IO_3^- + aI^- + bH⁺ → cH₂O + dI₂
a, b, c and d respectively corresponds to

• 5, 6, 3, 3

• 5, 3, 6, 3

• 3, 5, 3, 6

• 5, 6, 5, 5

Among the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other, in

• Tl⁺, Tl³⁺

• Cu⁺, Cu²⁺

• Cr²⁺, Cr³⁺

• V²⁺, VO²⁺