Science (English Medium) Class 11 - CBSE Question Bank Solutions

Dipole-dipole forces act between the molecules possessing permanent dipole. Ends of dipoles possess ‘partial charges’. The partial charge is ______.

Dihydrogen can be prepared on commercial scale by different methods. In its preparation by the action of steam on hydrocarbons, a mixture of \[\ce{CO}\] and \[\ce{H2}\] gas is formed. It is known as:

(i) Water gas.

(ii) Syngas.

(iii) Producer gas.

(d) Industrial gas.

Write one chemical reaction for the preparation of \[\ce{D2O2}\].

How do you account for the strong reducing power of lithium in aqueous solution?

Lithium resembles magnesium in some of its properties. Mention two such properties and give reasons for this resemblance.

All compounds of alkali metals are easily soluble in water but lithium compounds are more soluble in organic solvents. Explain.

Assertion (A): The carbonate of lithium decomposes easily on heating to form lithium oxide and CO₂.

Reason (R): Lithium being very small in size polarises large carbonate ion leading to the formation of more stable Li₂O and CO₂.

Lithium hydride can be used to prepare other useful hydrides. Beryllium hydride is one of them. Suggest a route for the preparation of beryllium hydride starting from lithium hydride. Write chemical equations involved in the process.

What is meant by hybridisation? Compound CH₂ = C = CH₂ contains sp or sp² hybridised carbon atoms. Will it be a planar molecule?

Which of the following will not show geometrical isomerism?

Alkynes on reduction with sodium in liquid ammonia form trans alkenes. Will the butene thus formed on reduction of 2-butyne show the geometrical isomerism?

Photochemical smog occurs in warm, dry and sunny climate. One of the following is not amongst the components of photochemical smog, identify it.

Which of the following statements is not true about classical smog?

Which of the following statements about photochemical smog is wrong?

From where does ozone come in the photochemical smog?

Assertion (A): Photochemical smog is oxidising in nature.

Reason (R): Photochemical smog contains NO₂ and O₃, which are formed during the sequence of reactions.

How can you apply green chemistry for the following:

To control photochemical smog.

Match the following prefixes with their multiples:-

Convert the following into basic units:

28.7 pm

Convert the following into basic units:

15.15 pm