Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEET 2009
Exam
NEET
Year
2009
Subject
Chemistry
Chapter
Thermodynamics (C)

NEET 2009 · Chemistry · Thermodynamics (C)

From the following bond energies : H-H bond energy : 431.37 ~kJ...

From the following bond energies : H−H\mathrm{H}-\mathrm{H} bond energy : 431.37 kJ mol−1431.37 \mathrm{~kJ} \mathrm{~mol}^{-1} C=C\mathrm{C}=\mathrm{C} bond energy : 606.10 kJ mol−1606.10 \mathrm{~kJ} \mathrm{~mol}^{-1} C−C\mathrm{C}-\mathrm{C} bond energy : 336.49 kJ mol−1336.49 \mathrm{~kJ} \mathrm{~mol}^{-1} C−H\mathrm{C}-\mathrm{H} bond energy : 410.50 kJ mol−1410.50 \mathrm{~kJ} \mathrm{~mol}^{-1} Enthalpy for the reaction, From the following bond energies : H-H bond energy : 431.37 ~kJ ~mol^ -1 C=C bond energy : 606.10 ~kJ ~mol^ -1 C-C bond
will be :

Options

  1. A553.0 kJ mol−1553.0 \mathrm{~kJ} \mathrm{~mol}^{-1}
  2. B1523.6 kJ mol−11523.6 \mathrm{~kJ} \mathrm{~mol}^{-1}
  3. C−243.6 kJ mol−1-243.6 \mathrm{~kJ} \mathrm{~mol}^{-1}
  4. D−120.0 kJ mol−1-120.0 \mathrm{~kJ} \mathrm{~mol}^{-1}

Correct answer

D. −120.0 kJ mol−1-120.0 \mathrm{~kJ} \mathrm{~mol}^{-1}

Step-by-step solution

\Delta \mathrm{H}=dissociation energy of reactant−Bonddissociationofenergyofproduct.reactant - Bond dissociation of energy of product.ΔH=(606.10+4×410.5+431.37)−(6×410.50+336.49)=−120.0kJ/mol\begin{aligned}\Delta \mathrm{H}=& (606.10+4 \times410.5+431.37) \\ & -(6 \times410.50+336.49) \\ & =-120.0 \mathrm{ kJ}/ \mathrm{mol} \end{aligned}$$
Practice Thermodynamics (C) on Quantrex Academy →

More from Thermodynamics (C)

A certain organic solvent has Δ H\_vap = 28.50\ kJ mol^ -1 and Δ S\_vap = 88.2\ J K^ -1 \… MHT CET Medical 2026Which of the following statements regarding spontaneous process is NOT true? MHT CET Medical 2026Calculate Δ H for a reaction, 2X_ (g) + Y_ (g) arrow 2Z_ (g) at 298 K if Δ U = -10.5 kJ… MHT CET Medical 2026500\ mL of nitrogen gas and 750\ mL hydrogen gas were allowed to react at 1\ bar pressure… MHT CET Medical 2026The relationship between Δ H and Δ U for the reaction, PCl_3(g) + Cl_2(g) arrow PCl_5(g)… MHT CET Medical 2026What would be the heat released in kJ when 450\ cm^3 of 0.02\ M\ H_2SO_4 is mixed with… MHT CET Medical 2026Identify from following reactions that it takes place with Δ H = Δ U . MHT CET Medical 2026Calculate the work done in the following reaction at 300\ K , A(g) + B(g) = 2C(g) [R =… MHT CET Medical 2026 Full Thermodynamics (C) list All NEET PYQs