The electronic configuration of elements A, B and C are [He] 2s¹, [Ne] 3s¹ and [Ar] 4s¹ respectively, which one of the following order is correct for the first ionization potentials (in kJ mol^-1) of A , B and C?

• A > B > C

• C > B > A

• B > C > A

• C > A > B

The catenation tendency of C, Si and Ge is in the order Ge < Si < C. The bond energies (in kJ mol^-1) of C-C, Si-Si and Ge-Ge bonds, respectively are

• 167, 180, 348

• 180, 167, 348

• 348, 167, 180

• 348, 180, 167

3.

Ionic radius (in Å) of As³⁺, Sb³⁺ and Bi³⁺ follow the order

• As³⁺ > Sb³⁺ > Bi³⁺

• Sb³⁺ > Bi³⁺ > As³⁺ 

• Bi³⁺ > As³⁺ > Sb³⁺

• Bi³⁺ > Sb³⁺ > As³⁺

The number of lone pairs of electrons present on : Xe in XeF₄ is

• 3

• 4

• 1

• 2

Which one of the following ions exhibits highest magnetic moment ?

• Cu²⁺

• Ti³⁺

• Ni²⁺

• Mn²⁺

The energy of an electron present in Bohr's second orbit of hydrogen atom is

• -1312 J atom^-1

• -328 kJ mol^-1

• -328 J mol^-1

• -164 kJ mol^-1

In the ground state, an element has 13 electrons in M shell. The element is

• copper

• chromium

• nickel

• iron

In a nuclide, one a.m.u. of mass is dissipated into energy to bind its nucleons. The energy equivalent of this mass is

• 931.5 eV

• 931.5 × 10⁶ eV

• 931.5 × 10⁶ MeV

• 931.5 MV

What is X in the following reaction ?

₁₂Mg²⁶ + ₁H² → ₁₂Mg²⁷ + X

• γ-ray

• ₀n¹

• ₁H¹

• ₁D²

Let electronegativity, ionisation energy and electron affinity be represented as EN, IP and EA respectively. Which one of the following equation is correct according to Mulliken?

• EN = IP × EA

• EN = $\frac{\mathrm{IP}}{\mathrm{EA}}$

• $\mathrm{EN}\hspace{0.17em}= \frac{\mathrm{IP}\hspace{0.17em}+ \mathrm{EA}}{2}$

• EN = IP - EA