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

Match the soaps given in Column I with items given in Column II.

Match the detergents given in Column I with their uses given in Column II.

Column I	Column II
(i)	(a) Dishwashing powder
(ii)	(b) Laundry soap
(iii) \[\ce{C17H33CO\overset{-}{O}\overset{+}{N}a + Na2CO3 + Rosin}\]	(c) Hair conditioners
(iv) \[\ce{CH3(CH2)16COO(CH2CH2O)nCH2CH2OH}\]	(d) Toothpaste

Assertion: Transparent soaps are made by dissolving soaps in ethanol.

Reason: Ethanol makes things invisible.

Assertion: Sodium chloride is added to precipitate soap after saponification.

Reason: Hydrolysis of esters of long-chain fatty acids by alkali produces soap in colloidal form.

Solutions of two electrolytes ‘A’ and ‘B’ are diluted. The Λ_m of ‘B’ increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte? Justify your answer. Graphically show the behavior of ‘A’ and ‘B’.

Convert the following:

Phenol to N-phenylethanamide.

The molar conductivity of CH₃COOH at infinite dilution is 390 Scm²/mol. Using the graph and given information, the molar conductivity of CH₃COOK will be:

Which of the following statements is not correct for amines?

Write the equations for the following reaction:

Phenol is treated with chloroform in the presence of NaOH

Molar conductivity of substance “A” is 5.9 × 10³ S/m and “B” is 1 × 10^–16 S/m. Which of the two is most likely to be copper metal and why?

Explain the following reaction:

Wolff-Kishner reduction

Give reasons for the following statement:

Copper does not displace hydrogen from acids.

Explain the following reactions:

Clemmensen reaction

Write the main product in the following reaction:

\[\ce{CH3CH2CHO ->[Zn(Hg)/Conc. HCl]}\]

Which of the following solutions of KCl will have the highest value of molar conductivity?

Assertion (A) : Conductivity decreases with decrease in concentration of electrolyte.

Reason (R) : Number of ions per unit volume that carry the current in a solution decreases on dilution.

Why ortho-nitrophenol is steam volatile while para-nitrophenol is not?

Write the chemical equation involved in the following reactions:

Acetylation of salicylic add

Write the structures of A, B and C in the following reaction:

Conductivity of 2 × 10⁻³ M methanoic acid is 8 × 10⁻⁵ S cm⁻¹. Calculate its molar conductivity and degree of dissociation if `∧_"m"^0` for methanoic acid, is 404 S cm² mol⁻³.