Class 12 Chemistry 2022 Board Exam

Define rate of reaction. Write two factors that affect the rate of reaction.

How will you carry out the following conversions : (Any two)
(i) Propanal to Propane
(ii) Ethanal to But-2-enal
(iii) Ethanoic acid to ethanamide

Predict the products formed when CH₃CH₂CHO reacts with the following reagents : (Any two)
(i) PhMgBr and then H₃O⁺
(ii) LiAlH₄
(iii) HCN

Predict the products formed when CH₃CHO reacts with the following reagents : (Any two)
(i) CH₃MgBr and then H₃O⁺
(ii) Zn(Hg)/Conc. HCl
(iii) Tollens' reagent

In the plot of molar conductivity (Λm) Vs. square root of concentration (√C), following curves are obtained for two electrolytes X and Y :
[Image of graph showing X as strong electrolyte and Y as weak electrolyte]
Answer the following :
(i) Predict the nature of electrolyte X and Y.
(ii) What happens on extrapolation of Λm to concentration approaching zero for electrolytes X and Y ?

Define molar conductivity for the solution of an electrolyte. How does it vary with concentration ?

The resistance and conductivity of a conductivity cell containing 0·001 M KCl solution at 298 K are 1200 Ω and 1·5 × 10⁻⁴ S cm⁻¹. Calculate its cell constant and molar conductivity.

In the given reaction
N₂ (g) + 3H₂ (g) ——→ 2NH₃ (g)
the rate of formation of NH₃ is 3·6 × 10⁻⁴ mol L⁻¹ s⁻¹. Calculate the
(i) rate of reaction, and
(ii) rate of disappearance of H₂ (g).

Arrange the following compounds as directed : (any Two)
(i) In decreasing order of basic strength in aqueous solution :
C₂H₅NH₂, (C₂H₅)₂ NH, (C₂H₅)₃ N
(ii) In increasing order of solubility in water :
(C₂H₅)₂ NH, C₂H₅NH₂, C₆H₅NH₂
(iii) In decreasing order of their pKb values :
C₆H₅NH₂, C₂H₅NH₂, NH₃

Write the Nernst equation for the following cell reaction :
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)
How will the Ecell be affected when concentration of
(i) Cu²⁺ ions is increased and
(ii) Zn²⁺ ions is increased ?