Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of___________________?

Related Mcqs:

1. Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400°C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg. K, entropy of saturated vapour = 7.2234 kJ/kg. K) The exit condition of steam is_______________?

   A. Superheated vapour
   B. Partially condensed vapour with quality of 0.9
   C. Saturated vapour
   D. Partially condensed vapour with quality of 0.1

2. The molar composition of a gas is 10% H2, 10% O2, 30% CO2 and balance H2O. If 50% H2O condenses, the final mole percent of H2 in the gas on a dry basis will be_______________?

   A. 10%
   B. 5%
   C. 18.18%
   D. 20%

3. High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process ?

   A. Δ H = 0 and ΔS = 0
   B. Δ H ≠ 0 and ΔS = 0
   C. Δ H ≠ 0 and ΔS ≠ 0
   D. Δ H = 0 and ΔS ≠ 0

4. Enthalpy of formation of NH3 is – 46 kJ/kg mole. The enthalpy change for the gaseous reaction, 2NH3 → N2 + 3H2, is equal to _____________ kJ/kg. mole?

   A. 46
   B. 92
   C. -23
   D. -92

5. The enthalpy change when ammonia gas is dissolved in water is called the heat of___________________?

   A. Solution
   B. Formation
   C. Dilution
   D. Combustion

6. Enthalpy change resulting, when unit mass of solid is wetted with sufficient liquid, so that further addition of liquid produces no additional thermal effect, is called the heat of________________?

   A. Mixing
   B. Adsorption
   C. Wetting
   D. Complete wetting

7. “The equilibrium value of the mole fraction of the gas dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid surface”. This statement pertaining to the solubility of gases in liquid is the ______________ law?

   A. Raoult’s
   B. Henry’s
   C. Amagat’s
   D. None of these

8. Forward reaction will be favoured for the exothermic reaction, represented by CO + H2O ⇌ CO2 + H2, by_________________?

   A. Low temperature and high pressure
   B. Low temperature and low pressure
   C. High temperature and high pressure
   D. High temperature and low pressure

9. Entropy change of mixing two liquid substances depends upon the_________________?

   A. Molar concentration
   B. Quantity (i.e. number of moles)
   C. Both A. and B
   D. Neither A. nor B

10. “If different processes are used to bring about the same chemical reaction, the enthalpy change is same for all of them”. This is ______________ law?

    A. Hess’s
    B. Kirchoff’s
    C. Lavoisier and Laplace
    D. None of these