Question

What is the general molecular formula of alkyl halides?

• A. \(\text{C}_n\text{H}_{2n+2}\text{X}\)
• B. \(\text{C}_n\text{H}_{2n+1}\text{X}\)
• C. \(\text{C}_n\text{H}_{2n}\text{X}\)
• D. \(\text{C}_n\text{H}_{2n-2}\text{X}\)

Hint:

Take an alkane CnH(2n+2) and replace one H with X.

Answer 1

The Correct Option is B

Step 1: Test with an example:
Ethyl bromide is $C_2H_5Br$. Here $n=2$ and hydrogens are 5.

Step 2: Compare:
$2n+1 = 5$, so $C_nH_{2n+1}X$ fits. The other formulae give 6, 4 or 2 hydrogens.

Step 3: Pick:
Option (B).

Final Answer:
Test with ethyl bromide, C2H5Br. \[ \boxed{B} \]