Bond lengths follow bond order and atomic size trends

Steps:

• Identify bonds in the oxime CH3CH=NOH: x labels C=N (double bond), y labels N-O (single bond), z labels C-C (single bond).
• Recall bond order rule: double bonds (C=N) are shorter than single bonds due to higher electron density.
• Compare single bonds: N-O (~1.46 Å) is shorter than C-C (~1.54 Å) because nitrogen and oxygen are smaller atoms than carbon.
• Order by increasing length: C=N (x) < N-O (y) < C-C (z).

Why A is correct:

• A (x y z) matches the trend where bond order decreases from double to single, and single bond length increases with atomic size.

Why the others are wrong:

• B: Places y (N-O) before x (C=N), but double bonds are always shorter than single bonds.
• C: Places z (C-C) before y (N-O), but N-O is shorter than C-C due to smaller atoms.
• D: Starts with y (N-O) as shortest, ignoring that C=N double bond is shorter.

Final answer: A