Science (English Medium) Class 12 - CBSE Question Bank Solutions for Chemistry

For a binary ideal liquid solution, the variation in total vapour pressure versus composition of solution is given by which of the curves?

Why is the vapour pressure of an aqueous solution of glucose lower than that of water?

Which of the statements about solutions of electrolytes is not correct?

\[\ce{\Lambda^0_m(NH4OH)}\] is equal to ______.

\[\ce{Λ^0_m H2O}\] is equal to:

(i) \[\ce{Λ^0_m_{(HCl)} + \ce{Λ^0_m_{(NaOH)} - \ce{Λ^0_m_{(NaCl)}}}}\]

(ii) \[\ce{Λ^0_m_{(HNO_3)} + \ce{Λ^0_m_{(NaNO_3)} - \ce{Λ^0_m_{(NaOH)}}}}\]

(iii) \[\ce{Λ^0_{(HNO_3)} + \ce{Λ^0_m_{(NaOH)} - \ce{Λ^0_m_{(NaNO_3)}}}}\]

(iv) \[\ce{Λ^0_m_{(NH_4OH)} + \ce{Λ^0_m_{(HCl)} - \ce{Λ^0_m_{(NH_4Cl)}}}}\]

Molar conductivity of ionic solution depends on:

(i) temperature.

(ii) distance between electrodes.

(iii) concentration of electrolytes in solution.

(iv) surface area of electrodes.

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.

When acidulated water (dil.H₂SO₄ solution) is electrolysed, will the pH of the solution be affected? Justify your answer.

Write the cell reaction of a lead storage battery when it is discharged. How does the density of the electrolyte change when the battery is discharged?

Why on dilution the m Λ_m of \[\ce{CH3COOH}\] increases very fast, while that of \[\ce{CH3COONa}\] increases gradually?

Match the items of Column I and Column II on the basis of data given below:

`E_("F"_2//"F"^-)^Θ` = 2.87 V, `"E"_(("Li"^(+))//("Li"^-))^Θ` = − 3.5V, `"E"_(("Au"^(3+))//("Au"))^Θ` = 1.4 V, `"E"_(("Br"_(2))//("Br"^-))^Θ` = 1.09 V

Assertion: Λ_m for weak electrolytes shows a sharp increase when the electrolytic solution is diluted.

Reason: For weak electrolytes degree of dissociation increases with dilution of solution.

Assertion: `"E"_("Ag"^+ //"Ag")` increases with increase in concentration of Ag⁺ ions.

Reason: `"E"_("Ag"^+ //"Ag")` has a positive value.

Assertion: Copper sulphate can be stored in zinc vessel.

Reason: Zinc is less reactive than copper.

Consider figure and answer the question to given below.

How will the concentration of Zn²⁺ ions and Ag⁺ ions be affected after the cell becomes ‘dead’?

Which of the following statements is incorrect about the collison theory of chemical reaction?

Which of the following statements are applicable to a balanced chemical equation of an elementary reaction?

(i) Order is same as molecularity.

(ii) Order is less than the molecularity.

(iii) Order is greater than the molecularity.

(iv) Molecularity can never be zero.

For a reaction A + B `->` Products, the rate law is — Rate = k [A][B]^3/2 Can the reaction be an elementary reaction? Explain.

Assertion: All collision of reactant molecules lead to product formation.

Reason: Only those collisions in which molecules have correct orientation and sufficient kinetic energy lead to compound formation.

All energetically effective collisions do not result in a chemical change. Explain with the help of an example.