Classification of Elements and Periodicity

Which of the following elements will have the lowest first ionisation energy?

Options

(a) Li (b) Mg (c) Ca (d) Rb

Correct Answer:

Rb

Explanation:

Rb belongs to I-A group and has maximum […]

When the first ionisation energies are plotted against atomic number, the peaks are occupied

Options

(a) alkali metals (b) halogens (c) transition metals (d) rare gases

Correct Answer:

rare gases

Explanation:

Rare gases […]

Pauling’s electro negativity values for elements are useful in predicting

Options

(a) Polarity of the molecules (b) Position in the E.M.F. series (c) Coordination numbers (d) Dipole moments

Correct Answer:

Polarity of the […]

Highest electron affinity is shown by

Options

(a) O⁻ (b) F⁻ (c) Cl₂ (d) F₂

Correct Answer:

O⁻

Explanation:

Molecules of F₂, Cl₂ and anion F⁻, all have stable inert has configuration. Thus, […]

Which of the following has the highest electron affinity?

Options

(a) F⁻ (b) O⁻ (c) O (d) Na

Correct Answer:

O

Explanation:

As the size of atom decreases, a larger amount of energy […]

The element, with atomic number 118, will be

Options

(a) alkali (b) noble gas (c) lanthanide (d) transition element

Correct Answer:

noble gas

Explanation:

Electronic configuration of element with atomic number 118 will […]

The ionisation energy of nitrogoen is more than that of oxygen because

Options

(a) nitrogen has half-filled p-orbitals (b) nitrogen is left ot the oxygen in the same period of the periodic table […]

Which of the following does not represent the correct order of the properties indicated

Options

(a) Ni²⁺> Cr²⁺> Fe²⁺> Mn²⁺(size) (b) Sc > Ti > Cr > Mn (size) (c) Mn²⁺ > Ni²⁺ […]