11.

Assertion: Co(IV) is known but Ni(IV) is not.             

Reason: Ni(IV) has d4 electronic configuration.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: The correct order of oxidising power is :

${\text{VO}}_2^{+}$ <  ${\text{Cr}}_2{O}_7^{2- }< MnO{ }_4^{-}$         

Reason: The oxidation state of Mn is +7

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : O₂ has higher bond length than O₃.

Reason: O₃ is paramagnetic.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Mixture of CH₃COOH and CH₃COONH₄ is an example of acidic buffer.

Reason: Acidic buffer contains equimolar mixture of weak acid and its salt with weak base.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both aaertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: All the hydrogen atoms in CH₄=C=CH₂ lie in one plane.

Reason : All the carbon atoms in its are sp² hybridized.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

The number of atoms in 52 g of He is

• 78.299 x 10²⁴atoms

• 7.820 x 10^-24atoms

• 7.829 x 10²⁴ atoms

• 78.234 x 10²⁵ atoms

KMnO₄ in alkaline medium changes to

• Mn³⁺

• MnO₂

• MnO${}_4^{2-}$

• Mn(OH)${}_4^{-}$

Which of the following has highest concentration of PAN?

• Smoke

• Ozone

• Photochemical smog

• Reducing smog

Which of the following reactions increases the production of dihydrogen from synthesis gas?

• ${\text{CH}}_{4_{\left(g\right)}}+H_2{O}_{\left(g\right) }\underset{Ni}{\overset{1270K}{\to }}C{O}_{\left(g\right)}+H_{2_{\left(g\right)}}$

• ${\text{C}}_{\left(s\right)}+H_2{O}_{\left(g\right)}\underset{}{\overset{1270 K}{\to }} C{O}_{\left(g\right)}+{H_2}_{\left(g\right)}$

• ${\text{CO}}_{\left(g\right)}+H_2{O}_{\left(g\right)}\underset{Catalyst}{\overset{637K}{\to }}C{O}_{2_{\left(g\right)}}+H_{2_{\left(g\right)}}$

• ${\text{C}}_2{H}_6+2H_{2}O \underset{Ni}{\overset{1270K}{\to }}2CO+5H_2$

The purity of an organic compound is determined by

• Chromatography

• Crystallisation

• melting or boiling point

• both( A )and (C)