Question:
Which of the following molecules contains maximum number of electrons in antibonding molecular orbitals?
Which of the following molecules contains maximum number of electrons in antibonding molecular orbitals?
Show Hint
Antibonding electrons increase as you move from $\text{N}_2 \to \text{O}_2 \to \text{F}_2$ in the second period.
Updated On: Apr 26, 2026
- $\text{Li}_2$
- $\text{N}_2$
- $\text{O}_2$
- $\text{F}_2$
Show Solution
Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Step 1: Configuration Analysis
We count electrons in $\sigma^*$, $\pi^*$ orbitals. - $\text{Li}_2$ ($6e^-$): $(\sigma 1s)^2 (\sigma^* 1s)^2 (\sigma 2s)^2$. Antibonding = 2. - $\text{N}_2$ ($14e^-$): $(\sigma 1s)^2 (\sigma^* 1s)^2 (\sigma 2s)^2 (\sigma^* 2s)^2 (\pi 2p_x)^2 (\pi 2p_y)^2 (\sigma 2p_z)^2$. Antibonding = 4. - $\text{O}_2$ ($16e^-$): Same as $\text{N}_2$ but plus $(\pi^* 2p_x)^1 (\pi^* 2p_y)^1$. Antibonding = 6. - $\text{F}_2$ ($18e^-$): Same as $\text{O}_2$ but plus $(\pi^* 2p_x)^2 (\pi^* 2p_y)^2$. Antibonding = 8.
Step 2: Comparison
$\text{F}_2$ has the highest number of electrons in antibonding orbitals.
Final Answer: (D)
We count electrons in $\sigma^*$, $\pi^*$ orbitals. - $\text{Li}_2$ ($6e^-$): $(\sigma 1s)^2 (\sigma^* 1s)^2 (\sigma 2s)^2$. Antibonding = 2. - $\text{N}_2$ ($14e^-$): $(\sigma 1s)^2 (\sigma^* 1s)^2 (\sigma 2s)^2 (\sigma^* 2s)^2 (\pi 2p_x)^2 (\pi 2p_y)^2 (\sigma 2p_z)^2$. Antibonding = 4. - $\text{O}_2$ ($16e^-$): Same as $\text{N}_2$ but plus $(\pi^* 2p_x)^1 (\pi^* 2p_y)^1$. Antibonding = 6. - $\text{F}_2$ ($18e^-$): Same as $\text{O}_2$ but plus $(\pi^* 2p_x)^2 (\pi^* 2p_y)^2$. Antibonding = 8.
Step 2: Comparison
$\text{F}_2$ has the highest number of electrons in antibonding orbitals.
Final Answer: (D)
Was this answer helpful?
0
0
Top MHT CET Chemistry Questions
- The temperature of $32^{\circ}C$ is equivalent to
- The heat of formation of water is $ 260\, kJ $ . How much $ H_2O $ is decomposed by $ 130\, kJ $ of heat ?
- If a metal crystallises in bcc structure with edge length of unit cell $4.29 \times 10^{-8}\, cm$ the radius of metal atom is
- Which of the following oxides can act both as an oxidising agent as well as reducing agent ?
- "The mass and energy both are conserved in an isolated system", is the statement of
View More Questions
Top MHT CET Biomolecules Questions
- Glucose gives silver mirror with ammoniacal silver nitrate because it has
- Glucose on oxidation gives the acid containing the C-chiral atoms equal to
- Glucose on reaction with Fehling solution gives
- A molecule of Stachyose contains how many carbon atoms ?
- Among the following, the formula of saturated fatty acid is
View More Questions
Top MHT CET Questions
- During r- DNA technology, which one of the following enzymes is used for cleaving DNA molecule ?
- In non uniform circular motion, the ratio of tangential to radial acceleration is (r = radius of circle, $v =$ speed of the particle, $\alpha =$ angular acceleration)
- The temperature of $32^{\circ}C$ is equivalent to
- The line $5x + y - 1 = 0$ coincides with one of the lines given by $5x^2 + xy - kx - 2y + 2 = 0 $ then the value of k is
- The heat of formation of water is $ 260\, kJ $ . How much $ H_2O $ is decomposed by $ 130\, kJ $ of heat ?
View More Questions