The heat of atomisation of met ... | Thermodynamics | JEE Main 2026

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JEE MAIN 2026

24-01-2026 S2

Question

The heat of atomisation of methane and ethane are ' $\mathrm{x}{ }^{\prime} \mathrm{kJmol}^{-1}$ and ' $\mathrm{y}{ }^{\prime} \mathrm{kJmol}^{-1}$ respectively. The longest wavelength $(\lambda)$ of light capable of breaking the $\mathrm{C}-\mathrm{C}$ bond can be expressed in SI unit as:

Select the correct option:

A

$\frac{\mathrm{hc}}{1000}\left(\frac{y-6 x}{4}\right)^{-1}$

B

$\frac{\mathrm{N}_{\mathrm{A}} \mathrm{hc}}{250(4 y-6 x)}$

C

$\frac{\mathrm{N}_{\mathrm{A}} \mathrm{hc}}{250(y-6 x)}$

D

$\mathrm{N}_{\mathrm{A}} \mathrm{hc}\left(y-\frac{6 x}{4}\right)^{-1}$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

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