Quantrex Academy · Free MHT CET PYQ solutions
MHT CET Chemistry Thermodynamics (C) 2026 MHT CET 2026 (17 April Shift 2)

MHT CET Chemistry Question (2026) — Solution

Question

Calculate the standard enthalpy of combustion of carbon monoxide if _f H^ ( CO ) = -110 kJ mol ^ -1 _f H^ ( CO _2) = -393 kJ mol ^ -1

Options

  1. A. -503 kJ mol ^ -1
  2. B. -110 kJ mol ^ -1
  3. C. -283 kJ mol ^ -1
  4. D. -383 kJ mol ^ -1

Answer

C. -283 kJ mol ^ -1

Step-by-step solution

The combustion reaction of carbon monoxide is given by: CO(g) + 1 2 O _2 (g) CO _2 (g) The standard enthalpy of combustion is calculated using the standard enthalpies of formation: _c H^ ( CO ) = _f H^ ( products ) - _f H^ ( reactants ) _c H^ ( CO ) = _f H^ ( CO _2) - [ _f H^ ( CO ) + 1 2 _f H^ ( O _2) ] Since the standard enthalpy of formation of O _2 in its standard state is zero: _c H^ ( CO ) = -393 - (-110 + 0) _c H^ ( CO ) = -393 + 110 = -283 kJ mol ^ -1 Answer: -283 kJ mol ^ -1

Practice more on Quantrex App →

Related: Chemistry — Thermodynamics (C) · All PYQ Banks