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

Which of the following polymers can have strong intermolecular forces?

(i) Nylon

(ii) Polystyrene

(iii) Rubber

(iv) Polyesters

Which factor imparts crystalline nature to a polymer like nylon?

Match the polymers given in Column I with their main applications given in Column II.

Assertion: Polyamides are best used as fibres because of high tensile strength.

Reason: Strong intermolecular forces (like hydrogen bonding within polyamides) lead to close packing of chains and increase the crystalline character, hence, provide high tensile strength to polymers

Which one of the following compounds is more reactive towards S_N1 reaction?

Which of the following tests/reactions is given by aldehydes as well as ketones?

Give reason for the following:

The product formed during S_N1 reaction is a racemic mixture.

A hydrocarbon (A) with molecular formula C₅H₁₀ on ozonolysis gives two products (B) and (C). Both (B) and (C) give a yellow precipitate when heated with iodine in presence of NaOH while only (B) give a silver mirror on reaction with Tollen’s reagent.

1. Identify (A), (B) and (C).
2. Write the reaction of B with Tollen’s reagent.
3. Write the equation for iodoform test for C.
4. Write down the equation for aldol condensation reaction of B and C.

Write chemical test to distinguish between the following compounds:

Phenol and Benzoic acid

What is the composition of Fehling's reagent?

In which reaction mechanism carbocation is formed?

Racemisation occurs in ______.

The vapour pressure of pure liquid X and pure liquid Y at 25°C are 120 mm Hg and 160 mm Hg respectively. If equal moles of X and Y are mixed to form an ideal solution, calculate the vapour pressure of the solution.

Assertion (A) : Nucleophilic substitution of iodoethane is easier than chloroethane.

Reason (R) : Bond enthalpy of C-I bond is less than that of C-Cl bond.

Arrange the following compounds in increasing order of reactivity towards S_N2 reaction.

2-Bromopentane, 1-Bromopentane, 2-Bromo-2-methylbutane

Retention of configuration is observed in ______.

An azeotropic mixture of two liquids will have a boiling point lower than either of the two liquids when it ______.

Inversion of configuration occurs in ______.

The reagent that can be used to distinguish acetophenone and benzophenone is ______.