Which of the following statements about the interstitial compounds is incorrect?

• They retain metallic conductivity

• They are chemically reactive

• They are much harder than the pure metal

• They have higher melting points than the pure metal

Which one of the following molecules contain no $\mathrm{\pi }$-bond?

• CO₂

• H₂O

• SO₂

• NO₂

6.02 x 10²⁰ molecules of urea are present in 100 mL of its solution. The concentration of solution is

• 0.02 M

• 0.01 M

• 0.001 M

• 0.1 M

KMnO₄ can be prepared from K₂MnO₄ as per reaction

  $3{\mathrm{MnO}}_4^{2-} + 2{\mathrm{H}}_2\mathrm{O} \rightleftharpoons 2{\mathrm{MnO}}_4^{-} + {\mathrm{MnO}}_2 + 4{\mathrm{OH}}^{-}$

The reaction can go to completion by removing OH- ions by adding

• HCl

• KOH

• CO₂

• SO₂

Which of the following structure is similar to graphite?

• BN

• B

• B₄C

• B₂H₆

The basic structural unit of silicates is

• SiO^-

• ${\mathrm{SiO}}_4^{4-}$

• ${\mathrm{SiO}}_3^{2-}$

• ${\mathrm{SiO}}_4^{2-}$

Identify the correct order of solubility in aqueous medium.

• CuS > ZnS > Na₂S

• ZnS > Na₂S > CuS

• Na₂S > CuS > ZnS

• Na₂S > ZnS > CuS

Which of the following is electron deficient?

• (CH₃)₂

• (SiH₃)₂

• (BH₃)₂

• PH₃

Which of these is not a monomer for a high molecular mass silicone polymer?

• MeSiCl₃

• Me₂SiCl₂

• Me₃SiCl

• PhSiCl₃

20.

The structure of isobutyl group in an organic compound is

• C₂H₆$-$CH$-$CH₂$-$

• ${\mathrm{CH}}_3-\underset{|}{\mathrm{CH}}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$

• ${\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-{\mathrm{CH}}_2-$

• ${\mathrm{CH}}_3-\mathrm{C}\left({\mathrm{C}}_2{\mathrm{H}}_6\right)-$