Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Chemistry

Arrange the following compounds in increasing order of acidity and give a suitable explanation.

Phenol, o-nitrophenol, o-cresol

Name the enzymes and write the reactions involved in the preparation of ethanol from sucrose by fermentation.

Dipole moment of phenol is smaller than that of methanol. Why?

The carbon-oxygen bond in phenol is slightly stronger than that in methanol. Why?

Arrange water, ethanol and phenol in increasing order of acidity and give reason for your answer.

Match the items of column I with items of column II.

Match the items of column I with items of column II.

Assertion: Ethanol is a weaker acid than phenol.

Reason: Sodium ethoxide may be prepared by the reaction of ethanol with aqueous \[\ce{NaOH}\].

The correct order of increasing acidic strength is ______.

In the nitration of benzene using a mixture of conc. \[\ce{H2SO4}\] and conc. \[\ce{HNO3}\], the species which initiates the reaction is ______.

What is the role of \[\ce{HNO3}\] in the nitrating mixture used for nitration of benzene?

A solution contains 1 g mol. each of p-toluene diazonium chloride and p-nitrophenyl diazonium chloride. To this 1 g mol. of alkaline solution of phenol is added. Predict the major product. Explain your answer.

Assertion: N, N-Diethylbenzene sulphonamide is insoluble in alkali.

Reason: Sulphonyl group attached to nitrogen atom is strong electron-withdrawing group.

Which of the following acids is a vitamin?

Each polypeptide in a protein has amino acids linked with each other in a specific sequence. This sequence of amino acids is said to be ______.

Lysine, \[\begin{array}{cc}
\ce{H2N - (CH2)4 - CH - COOH}\\
\phantom{.....}|\\
\phantom{........}\ce{NH2}
\end{array}\] is:

(i) α-Amino acid

(ii) Basic amino acid

(iii) Amino acid synthesised in body

(iv) β-Amino acid

Amino acids can be classified as α–, β–, γ–, δ– and so on depending upon the relative position of amino group with respect to carboxyl group. Which type of amino acids form polypetide chain in proteins?

Amino acids behave like salts rather than simple amines or carboxylic acids. Explain.

Describe the term D- and L- configuration used for amino acids with examples.

Which of the following polymer is biodegradable?