Why is free rotation about a $\mathrm{\pi }-$bond not possible?

Important Questions on Chemical Bonding and Molecular Structure

MEDIUM

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 2

Compare the shapes of a $\mathrm{p}$-orbital and $\mathrm{sp}$-orbital. Which one has a greater directional orientation and why?

HARD

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 3

Discuss the hybridization of carbon atoms in allene$\left({\mathrm{C}}_3{\mathrm{H}}_4\right)$ and show that $\mathrm{\pi }$-orbital overlaps.

MEDIUM

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 4

Compare the shapes of a $\mathrm{p}$-orbital and an $\mathrm{sp}$-hybrid orbit. Which one has a greater directional orientation? Explain.

EASY

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 5

The carbon-carbon double bond energy in ${\mathrm{C}}_2{\mathrm{H}}_4$ is $615 \mathrm{kJ}/\mathrm{mol}$ and the carbon-carbon single bond energy in ${\mathrm{C}}_2{\mathrm{H}}_6$ is $347 \mathrm{kJ}/\mathrm{mol}$. Why is the double bond energy appreciably less than twice the single bond energy?

EASY

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 5

The two $-{\mathrm{CH}}_2$ groups in ${\mathrm{C}}_2{\mathrm{H}}_4$ do not rotate freely around the bond connecting them, although the two $-{\mathrm{CH}}_3$ groups in ${\mathrm{C}}_2{\mathrm{H}}_6$ have almost an unhindered rotation around the $\mathrm{C}-\mathrm{C}$ bond. Why?

EASY

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 6

Which $\mathrm{p}$-orbitals overlapping would give the strongest bond?

MEDIUM

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 7

Ratio of $\sigma$ and $\pi$ bonds is maximum in:

EASY

JEE Advanced

IMPORTANT

Chapterwise/Topicwise Daily Practice Problems (DPP) Inorganic Chemistry Part - 1 JEE Main & Advanced>Chapter 2 - Chemical Bonding and Molecular Structure>DPP>Q 8

$\mathrm{HCN}$ and $\mathrm{HNC}$ molecules have an equal number of: