Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
KVPY2018ChemistryThermodynamics (C)

The quantity of heat (in J ) required to raise the temperature of 1 . 0   k g of ethanol from 293 . 45   K to the boiling point and then change the liquid to vapor at that temperature is closest to [Given, boiling point of ethanol 351 . 45   K . Specific heat capacity of liquid ethanol 2 . 44   J   g - 1   K - 1 . Latent heat of vaporisation of ethanol 855   J g - 1 ]

Options

  1. A142 × 10 2
  2. B9 . 97 × 10 2
  3. C142 × 10 5
  4. D9 . 97 × 10 5

Correct answer

D. 9 . 97 × 10 5

Step-by-step solution

Given, mass of ethanol = 1   k g = 1000   g Latent heat of vaporisation of ethanol = 855   J g - 1 Specific heat capacity of ethanol = 2 . 44   J / g k - 1 Heat, q = m c   Δ   T + heat of vaporisation = 1000 × 2 . 44   ( 351 . 45 - 293 . 45 ) + 855 × 1000   J = 9 . 97 × 10 5   J

Practice Thermodynamics (C) on Quantrex Academy →

More from Thermodynamics (C)

Identify the INCORRECT statement 2026The standard enthalpies of formation of CH₄ (g), CO₂ (g) and H₂ O(l) are -74.8 kJ mol ⁻¹ , -393.5 kJ mol ⁻¹ and -285.8 kJ mol ⁻¹ respectively. Then the enthalpy change for the give 2026For an ideal gas undergoing an isothermal change, there is 2026Ozone is formed by the reaction O _ 2(g) + O _ (g) O _ 3(g) , H = -107.2 kJ . Given O=O bond energy is 498.0 kJ mol ⁻¹ , the average bond energy of ozone is: 2026H and S for a reaction are 35.5 kJ mol ⁻¹ and 83.6 J K ⁻¹ respectively. Assuming that H and S do not vary with temperature, the reaction is spontaneous when: 2026The heat of combustion of carbon to CO ₂ is -393.5 kJ mol ⁻¹ . The heat released on the formation of 35.2 g of CO ₂ by combustion of C is: 20265 moles of a gas is allowed to pass through a series of changes as shown in the graph, in a cyclic process. The processes C A , B C and A B respectively are 20251 mole of an ideal gas is allowed to expand isothermally and reversibly from 1 L to 5 L at 300 K. The change in enthalpy (in kJ ) is ( R =8.3 ~J ~K ⁻¹ ~mol ⁻¹ ) 2025 Full Thermodynamics (C) list All KVPY PYQs