NEET 2025 · ChemistryPrevious Year Question

$C (s) + 2 H X_{2} (g) CH X_{4} (g)$ ; $Δ H = - 74.8 k J m o l^{- 1}$ . Which of the following diagrams gives an accurate representation of the above reaction? [R $\to$ reactants; P $\to$ products]

Answer: (C) Energy-level diagram: reactants (R) at higher energy, an activation hump, and products (P) at lower energy than R — exothermic.. \textbf{Answer:} (C) \textbf{Solution:} $Δ H = - 74.8 k J m o l^{- 1} < 0$ , so the reaction is exothermic: energy is released and the products lie at lower energy than the reactants.

NEET 2025 Chemistry question — C(s) + 2H2(g) -> CH4(g); H = -74.8 kJ,mol-1. Which of the following diagrams gives an…

A.Energy-level diagram: reactants (R) and products (P) at nearly the same level with P only marginally below R.
B.Energy-level diagram: products (P) at higher energy than reactants (R), endothermic.
C.Energy-level diagram: reactants (R) at higher energy, an activation hump, and products (P) at lower energy than R — exothermic.✓
D.Energy-level diagram: products (P) at a higher peak than reactants (R).

Correct Answer

(C) Energy-level diagram: reactants (R) at higher energy, an activation hump, and products (P) at lower energy than R — exothermic.

Solution & Explanation

\textbf{Answer:} (C) \textbf{Solution:} $Δ H = - 74.8 k J m o l^{- 1} < 0$ , so the reaction is exothermic: energy is released and the products lie at lower energy than the reactants. Only diagram (C) shows P below R (reactants higher, products lower, with the energy released equal to $74.8 k J m o l^{- 1}$ ). Mapped: source lowercase answer 'c' → option C.

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C(s)+2HX2​(g)​CHX4​(g); ΔH=−74.8 kJmol−1. Which of the following diagrams gives an accurate representation of the above reaction? [R → reactants; P → products]

Solution & Explanation

More NEET PYQ solutions

$C (s) + 2 H X_{2} (g) CH X_{4} (g)$ ; $Δ H = - 74.8 k J m o l^{- 1}$ . Which of the following diagrams gives an accurate representation of the above reaction? [R $\to$ reactants; P $\to$ products]