Related Mcqs:

1. For the irreversible reaction, Ca+ 2C = Ca C2 , Δ H°298 = – 60000 J . mole-1 . If a system initially containing 2 moles of calcium, 3 moles of carbon and 1 mole of calcium carbide is allowed to react to completion, the heat evolved at 298 K will be__________________?

   A. 30,000 J
   B. 60,000 J
   C. 90,000 J
   D. 2,40,000 J

2. The heat released by cooling one mole of copper from 400 K to room temperature (300 K) is (assume : Cp of copper is 23 J K-1mole-1) ?

   A. 2300 J
   B. 4600 J
   C. 230 J
   D. 2.3 × 106 J

3. Melting point & boiling points of liquid oxygen are respectively – 218.8°C & – 183°C, while the same for liquid nitrogen is – 210°C & – 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8 ?

   A. °C
   B. °F
   C. °K
   D. °R

4. Consider an ideal solution of components A and B. The entropy of mixing per mole of an alloy containing 50% B is_______________?

   A. R ln 2
   B. -R ln 2
   C. 3 R ln 2
   D. -3R ln 2

5. Natural water contains approximately ______________ percent of heavy water?

   A. 0.015
   B. 0.71
   C. 1.2
   D. 3.5

6. Heat transfer to the water wall in a high pressure water wall type boiler furnace is mainly by_________________?

   A. Conduction
   B. Convection
   C. Radiation
   D. Both A. & B.

7. Absolute zero, pressure will occur, when the molecular momentum of the system becomes zero. A liquid will cease to exist as liquid at________________?

   A. High vacuum
   B. Zero pressure
   C. 0°K
   D. Earth’s centre

8. The efficiency of a Carnot heat engine operating between absolute temperatures T1 and T2 (when, T1 > T2) is given by (T1 – T2)/T1. The co-efficient of performance (CO.P.) of a Carnot heat pump operating between T1 and T2 is given by_________________?

   A. T1/(T1-T2)
   B. T2/(T1-T2)
   C. T1/T2
   D. T2/T1

9. A gas which is collected over water becomes moistened due to water vapor, exerts its own partial pressure at the gas temperature, which is termed as its_______________?

   A. Aqueous tension
   B. Saturated humidity
   C. Vapor pressure
   D. Absolute humidity

10. In the X-ray radiography technique, the tube voltage for thicker plates as compared to thin plates, should be________________?

    A. Higher, as it gives higher wavelength
    B. Lower, as it gives higher wavelength
    C. Higher, as it gives shorter wavelength
    D. Lower, as it gives shorter wavelength