Assertion : Cuprous ion $\left({\mathrm{Cu}}^{+}\right)$ is colourless whereas cupric ion $\left({\mathrm{Cu}}^{2+}\right)$ produces blue colour in solution.

Reason : Cuprous ion $\left({\mathrm{Cu}}^{+}\right)$ has unpaired electrons while cupric ion $\left({\mathrm{Cu}}^{2+}\right)$ does not.

Assertion: To a solution of potassium chromate if a strong acid is added it changes its colour from yellow to orange.

Reason : The colour change is due to the oxidation of potassium chromate.

Assertion: Transition metals have high boiling points and high enthalpy of atomization.

Reason: The transition metals occur in bcc, hcp or ccp structures charcterstics of metals.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion
3. Assertion is true but reason is false
4. Both assertion and reason are false

Assertion: Zn, Cd and Hg are normally not considered transition metals.

Reason: d-orbitals in above elements are completely filled, hence above metals do not show the general charcterstic properties of the transition elements.

Assertion :A transition metal forms alloy with other transition metal easily.

Reason: The transition metals have similar electronic configuration,nearly equal radii and exhibit similar packing in their lattices.

Assertion: E^o for Mn³⁺/Mn²⁺ couple is more positive than for Fe³⁺/Fe²⁺.

Reason: Mn³⁺ has d⁴ configuration and Fe³⁺ has a d⁵ configuration.

Assertion: Transition metals exhibit higher enthalpies of atomization.

Reason: The atoms of transition metals are held together by strong metallic bonds.

Assertion : The transition elements form interstitial compounds.

Reason: Steel and cast iron are hard due to the formation of an interstitial compound with carbon.