Science (English Medium) कक्षा ११ - CBSE Question Bank Solutions

Why are BeSO4 and MgSO₄ readily soluble in water while CaSO₄, SrSO₄ and BaSO₄ are insoluble?

What is the structure of BeCl₂ molecule in gaseous and solid state?

Assertion (A): Beryllium carbonate is kept in the atmosphere of carbon dioxide.

Reason (R): Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide.

An element of group 2 forms covalent oxide which is amphoteric in nature and dissolves in water to give an amphoteric hydroxide. Identify the element and write chemical reactions of the hydroxide of the element with an alkali and an acid.

Which of the following is a Lewis acid?

Catenation i.e., linking of similar atoms depends on size and electronic configuration of atoms. The tendency of catenation in Group 14 elements follows the order:

The reason for small radius of Ga compared to Al is:

(i) poor screening effect of d and f orbitals.

(ii) increase in nuclear charge.

(iii) presence of higher orbitals.

(iv) higher atomic number.

The linear shape of CO₂ is due to:

(i) sp³ hybridisation of carbon.

(ii) sp hybridisation of carbon.

(iii) pπ – pπ bonding between carbon and oxygen.

(iv) sp² hybridisation of carbon.

Give reasons for the following:

CCl₄ is immiscible in water, whereas SiCl₄ is easily hydrolysed.

Explain the following:

Silicon forms \[\ce{SiF^{2-}6}\] ion whereas corresponding fluoro compound of carbon is not known.

Explain the following:

CO₂ is a gas whereas SiO₂ is a solid.

Explain the following:

Silicon forms \[\ce{SiF^{2-}6}\] ion whereas corresponding fluoro compound of carbon is not known.

The +1 oxidation state in group 13 and +2 oxidation state in group 14 becomes more and more stable with increasing atomic number. Explain.

Carbon and silicon both belong to the group 14, but inspite of the stoichiometric similarity, the dioxides, (i.e., carbon dioxide and silicon dioxide), differ in their structures. Comment.

Explain the following:

Carbon shows catenation property but lead does not.

Explain the following:

BF₃ does not hydrolyse.

Explain the following:

Why does the element silicon, not form a graphite like structure whereas carbon does.

A tetravalent element forms monoxide and dioxide with oxygen. When air is passed over heated element (1273 K), producer gas is obtained. Monoxide of the element is a powerful reducing agent and reduces ferric oxide to iron. Identify the element and write formulas of its monoxide and dioxide. Write chemical equations for the formation of producer gas and reduction of ferric oxide with the monoxide.

Which of the following is the correct IUPAC name?

The IUPAC name for