The NMR spectrum of AX, exhibits lines at $\delta=2.1$ and 2.3 ppm (for X type protons) and = 4.1, 4.3, 4.5 and 4.7 ppm (for A type protons), measured from TMS with an instrument operating at 100 MHz. The chemical shift (in ppm) of A and X protons and coupling constant in (Hz) are respectively.
(a)4.4, 2.2 and 20
(b)2.2, 4.4 and 10
(c)2.2, 4.4 and 5
(d)4.3, 2.1 and 2
Answer
Answer: A ✓ checked by 4AB · confidence high
Explanation
The X doublet is centred at 2.2 ppm and the A quartet at 4.4 ppm. The line spacing is 0.2 ppm × 100 MHz = 20 Hz (a).