NEET Chemical Bonding and Molecular Structure — Set 18

Question 1

Which molecule has a bent shape due to the presence of lone pairs?

Accepted Answer

In $ \ce{H2O} $, oxygen has two lone pairs and two bonding pairs, resulting in a bent shape with a bond angle of 104.5°.

Question 2

Which of the following species has a bond order of 2?

Accepted Answer

For $ \ce{O2} $: $ (\sigma 1s)^2 (\sigma^* 1s)^2 (\sigma 2s)^2 (\sigma^* 2s)^2 (\sigma 2p_z)^2 (\pi 2p_x)^2 (\pi 2p_y)^2 (\pi^* 2p_x)^1 (\pi^* 2p_y)^1 $. Bonding electrons = 10, antibonding = 6. Bond order = $ \frac{10 - 6}{2} = 2 $.

Question 3

The bond order of $ \ce{O2^2-} $ ion, based on molecular orbital theory, is:

Accepted Answer

For $ \ce{O2^2-} $ (18 electrons): $ (\sigma 1s)^2 (\sigma^* 1s)^2 (\sigma 2s)^2 (\sigma^* 2s)^2 (\sigma 2p_z)^2 (\pi 2p_x)^2 (\pi 2p_y)^2 (\pi^* 2p_x)^2 (\pi^* 2p_y)^2 $. Bonding = 10, antibonding = 8. Bond order = $ \frac{10 - 8}{2} = 1 $.

NEET Chemistry: Chemical Bonding and Molecular Structure — Practice Set 18

Q1. Which molecule has a bent shape due to the presence of lone pairs?

Q2. Which of the following species has a bond order of 2?

Q3. The bond order of \( \ce{O2^2-} \) ion, based on molecular orbital theory, is:

Q4. The total number of sigma and pi bonds in \( \ce{C5H8} \) (1,3-pentadiene, \( \ce{CH2=CH-CH=CH-CH3} \)) is:

Q5. Which molecule contains a triple bond and has a bond length of approximately 120 pm?

Q6. Which molecule contains a coordinate bond where nitrogen donates a lone pair to boron?

Q7. Which molecule has a bond order of 3 and is diamagnetic?

Q8. The number of sigma bonds in \( \ce{C2H6} \) molecule is:

Q9. Which molecule exhibits hydrogen bonding and has a bond angle of approximately 104.5°?

Q10. The number of pi bonds in \( \ce{C4H6} \) (butadiene, \( \ce{CH2=CH-CH=CH2} \)) is: