Question

Identify the compound which shows mass spectrum: $m/z = 60$ (100%), $m/z = 61$ (3%), $m/z = 62$ (0.2%)

• A.

  

• B. n-Propanol ($CH_3CH_2CH_2OH$)
• C. Glycolaldehyde ($CHO-CH_2-OH$)
• D. $N_4H_4$

Hint:

Carbon = 12, Oxygen = 16, Nitrogen = 14. Add them up to find the base $m/z$!

Answer 1

The Correct Option is B

Step 1: Concept Mass spectrometry identifies molecules by their mass-to-charge ratio ($m/z$).

Step 2: Meaning The molecular weight of the compound must be 60.

Step 3: Analysis Let's check molecular weights: n-Propanol ($C_3H_8O$): $(3\times12) + (8\times1) + 16 = 36 + 8 + 16 = 60$. Glycolaldehyde ($C_2H_4O_2$): $(2\times12) + (4\times1) + (2\times16) = 24 + 4 + 32 = 60$. However, n-propanol is the standard example that matches the isotopic distribution ($M+1, M+2$) shown.

Step 4: Conclusion n-Propanol fits the data perfectly. Final Answer: (2)