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

Account for the following:

Copper has an exceptionally positive `"E"_("M"^(2+)//"M")^0` value.

Account for the following:

Eu²⁺ with electronic configuration [Xe]4f⁷6s² is a strong reducing agent.

The trend of which property is represented by the following graph?

In order to protect iron from corrosion, which one will you prefer as a sacrificial electrode, Ni or Zn? Why? (Given standard electrode potentials of Ni, Fe and Zn are -0.25 V, -0.44 V and -0.76 V respectively.)

The second ionization enthalpies of chromium and manganese are 1592 and 1509 kJ/mol respectively. Explain the lower value of Mn.

Give two similarities in the properties of Sc and Zn.

What is the oxidation state of chromium in chromate ion and dichromate ion?

Write the ionic equation for reaction of KI with acidified KMnO₄.

Calculate the standard cell potential of a galvanic cell in which the following reaction takes place:

\[\ce{Fe{^{2+}_{(aq)}} + Ag{^{+}_{(aq)}} -> Fe{^{3+}_{(aq)}} + Ag_{(s)}}\]

Calculate the Δ_rG° and equilibrium constant of the reaction.

Why are interstitial compounds well known for transition metals?

Describe the oxidising action of potassium dichromate and write the ionic equation for its reaction with iron (II) solution.

Describe the oxidising action of potassium dichromate and write the ionic equation for its reaction with H₂S.

For M²⁺/M and M³⁺/M²⁺systems, the E^Θ values for some metals are as follows:

Use this data to comment upon:

The ease with which iron can be oxidised as compared to a similar process for either chromium or manganese metal.

Decide which of the following atomic numbers are the atomic numbers of the inner transition elements:

29, 59, 74, 95, 102, 104

Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:

Oxidation states

Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:

Ionisation enthalpies

Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:

Atomic sizes

Write the structure of the compound whose IUPAC name is as follows:

4-Chloro-3-ethylbutan-1-ol

How will you convert: Propene to Propan-2-ol?

Write the chemical equation involved in the following reaction:

Hoffmann-bromamide degradation reaction