111.

Which one of the following elements belongs to s-block?

• Aluminium

• Chromium

• Carbon

• Potassium

Which one is the correct decreasing order of the ionic radii of the ions?

• N^3- > O^2-> F^- > Na⁺

• N^3-> Na⁺> O^2- > F^-

• Na⁺ >O^2-> N^3-> F^-

• Na⁺> F^-> O^2->N^3-

The ionic radii of N^3-, O^2-, F^- and Na⁺ follow the order

• N^3- > O^2- > F^- > Na⁺

• N^3- > Na⁺ > O^2- > F^-

• Na⁺ > O^2- > N^3- > F^-

• O^2- > F^- > Na⁺ > N^3-

18 carat gold contains

• 18% gold

• 24% gold

• 75% gold

• 60% gold

Which of the following metals will not form an amalgam?

• Gold

• Silver

• Zinc

• Iron

The element which liberates oxygen gas from water is

• P

• Na

• F

• I

The strongest oxidising agent amongst F₂, Cl₂, Br₂ and I₂ is

• F₂

• I₂

• Cl₂

• Br₂

Which of the following is an organo-metallic compound?

• Lithium ethoxide

• Ethyl lithium

• Lithium acetate

• Lithium carbide

Electronic configuration of H⁺ is

• 1s⁰

• 1s¹

• 1s²

• 1s¹, 2s¹

Pick out the isoelectronic structures from the following

$\underset{\mathrm{I}}{{\mathrm{CH}}_3^{+}} \underset{\mathrm{II}}{{\mathrm{H}}_3{\mathrm{O}}^{+}} \underset{\mathrm{III}}{{\mathrm{NH}}_3} \underset{\mathrm{IV}}{{\mathrm{CH}}_3^{-}}$

• I and II

• I and IV

• I and III

• II, III and IV