STEAM MULTIPLE CHOICE QUESTIONS (MCQ) WITH ANSWERS

STEAM MULTIPLE

CHOICE QUESTIONS

(MCQ) WITH ANSWERS  

MCQ help to understand a topic in depth.

 It helps in the operation of a steam device.

It helps in trouble shooting.

  1.  Water consumes  heat on rise of temperature

  • (a) Latent heat

  • (b) Enthalpy

  • (c) Sensible heat

  • (d) None

ANS: ©

  1.  Water consumes heat without rise of temperature

  • (a) Latent heat

  • (b) Enthalpy

  • (c) Sensible heat

  • (d) None

ANS(a)

  1. Dryness fraction of dry saturated steam on heating

  • (a) Increase

  • (b) Decreases

  • (c) Remains same

  • (d) None

ANS: ©

  1. Water at atmospheric pressure is a

    • (a) Ideal gas

    • (b) Far below the critical temperature

    • (c) Far above the critical temperature

    • (d) None

ANS: (b)

  1. The latent heat of steam at the atmospheric pressure is

    • (a) 2157 k J/kg

    • (b) 2257 k J/kg

    • (c)2457 k J/kg

    • (d) None

ANS: (b)

  1. Volume of steam is approximately

    • (a) 600 times that of water

    • (b) 800 times that of water

    • (c) 1000 times that of water

    • (d) None

ANS: (b)

  1. Internal energy is with respect to

    • (a) Constant pressure

    • (b) Constant volume

    • (c) Constant temperature

    • (d) None

ANS: (b)

  1. Sensible heat of water up to 1000C

    • (a) > the latent heat of steam

    • (b) < the latent heat of steam

    • (c) = to the latent heat of steam

    • (d) None

ANS:(b)

  1. Critical temperature and critical pressure of steam is

    • (a) 2 0C and 374.15 Bar

    • (b) 15 0C and 374.15 bar

    • (c) 15 0C and 221

    • (d) None

ANS: (c)

  1. With the increase of pressure, the boiling point of water

    • (a) Increases

    • (b) Decreases

    • (c) No change

    • (d) None

ANS: (a)

  1. Specific internal energy of dry steam equals

    • (a)  u= h g + 100 p v g

    • (b) u = h g – 100 p v g

    • (c) u = 100 h g/p  v g

    • (d) None

ANS: (b)

  1. What is effect of increase of pressure on the enthalpy of steam

    • (a) Increases

    • (b) Decreases

    • (c) Remains same

    • (d) None

ANS: (b)

  1. Dryness fraction of steam is equal to

    • (a) m water/(m water + m dry steam)

    • (b) m dry steam/ (m water + m dry steam)

    • (c) (m water + m dry steam)/ m dry steam

    • (d) None

ANS: (b)

  1. Specific enthalpy of wet steam is

    • (a) h= h water + x h steam

    • (b) h = h water — x h steam

    • (c) h= (1—x) h water + x h steam

    • (d) None

ANS: ©

  1. Effect of increase of pressure on the specific volume of water is

    • (a) Increases

    • (b) Decreases

    • (c) Remains the same

    • (d) None

ANS: ©

  1. Measure more accurate dryness fraction of steam with

    • (a) Separating Calorimeter

    • (b) Throttling Calorimeter

    • (c) Separating and throttling Calorimeter

    • (d) None

ANS: ©

  1. Saturation temperature of water at 2 atm is

    • (a) 120 C

    • (b) 110 C

    • (c) 100 C

    • (d) None

ANS: (a)

  1.  Super-heating of steam consumes

    • (a) Latent heat

    • (b) Sensible heat

    • (c)  Sensible and latent heat

    • (d) None

ANS: (b)

  1. The dryness fraction of super-heated steam is

    • (a) =1

    • (b) <1

    • (c) >1

    • (d) None

ANS: (a)

  1. Enthalpy of dry saturated steam is

    • (a) = to the enthalpy of wet steam

    • (b) <  the enthalpy of wet steam

    • (c) > the enthalpy of wet steam

    • (d) None

ANS:  ©

21. Boiling point of water at 2 bar is

(a) 1000C

(b) 1100C

(c) 1200C

(d) None

Ans: (c)

22. The triple point temperature  of water is

(a) -56.20C

(b) 0.010C

(c) 374.150C

(d) None

Ans: (b)

23. The critical temperature  of water is

(a) -56.20C

(b) 0.010C

(c) 374.150C

(d) None

Ans: (c)

24. The critical pressure of water is

(a) 7.38 MPa

(b) 22.12 MPa

(c) 5.04 MPa

(d) None

Ans: (b)

25. The triple point pressure of water is

(a) 611.2  Pa

(b) 611.2 MPa

(c) 611.2 kPa

(d) None

Ans: (c)

26. The latent heat of fusion of ice is

(a) 2257 kJ/kg

(b) 335 kJ/kg

(c) 535 kJ/kg

(d) None

Ans: (b)

27. The latent heat of vaporization of water is

(a) 2257 kJ/kg

(b) 335 kJ/kg

(c) 535 kJ/kg

(d) None

Ans: (a)

28. What is degree of super-heat?

(a) The temperature above the freezing point

The temperature above the boiling point

(c) The temperature above 00C

(d) None

Ans: (b)

29. Dryness fraction is

(a) Ratio of mass of water present to mass of water-steam mixture

(b) Ratio of mass of vapor present to mass of water-steam mixture

(c) Amount of vapor present to the mass of water

(d) None

Ans: (b)

30. Sensible heat of water is

(a) m Cp dt

(b) m hfg

(c) m cv dt

(d) None

Ans: (a)

31. Addition of heat due to super-heating is

(a) m c pv (t steam–0)

(b) m c pv (t steam–t saturation)

(c) m hfg

(d) None

Ans: (b)

32. Entropy of water at 100C will be

(a) cp ln (10/100)

(b) cp ln (273/283)

(c) cp ln (283/273)

(d) None

Ans: (c)

33. Entropy of vaporization is

(a) 100/h fg

(b) h fg/T satu

(c) 2257/1000C

(d) None

Ans: (b)

34. Represent a  throttling process on the enthalpy entropy chart by a

(a) Horizontal line

(b) Vertical line

(c) Inclined line

(d) None

Ans: (a)

35. Represent a reversible adiabatic process on the enthalpy entropy

chart by a

(a) Horizontal line

(b) Vertical line

(c) Inclined line

(d) None

Ans: (b)

36. The specific enthalpy of water at 500C will be

(a) 50 kJ

(b) 105 kJ

(c) 210 kJ

(d) None

Ans: (c)

37. The specific enthalpy of water at 10 bar and at 500C will be

(a) 50 kJ

(b) 105 kJ

(c) 210 kJ

(d) None

Ans: (c)

38. The boiling temperature of water

(a) Increases with the decrease of pressure

(b) Decreases with the decrease of pressure

(c) remains constant with the change of pressure

(d) None

Ans: (b)

39. The boiling temperature of Freon -22

(a) Increases with the decrease of pressure

(b) Decreases with the decrease of pressure

(c) remains constant with the change of pressure

(d) None

Ans: (b)

40. The latent heat of vaporization of water decreases with the

(a) Increase of pressure

(b) Decrease of boiling temperature

(c) Decrease of pressure

(d) None

Ans: (a)

41. The specific enthalpy of saturated steam decreases with the

(a) Increase of pressure

(b) Decrease of boiling temperature

(c) Decrease of pressure

(d) None

Ans: (c)

42. Volume of water on heating above 0 0C

(a)  Increases

(b) Decreases

(c) Does not change at all

(d) none

Ans: (b)

43. Measure the high dryness fraction of wet steam with the help of a

(a) Separating Calorimeter

(b) Throttling Calorimeter

Combined separating and Throttling Calorimeter

(d) none

Ans: (b)

44. The phase change from liquid to vapor is

(a) Drop wise Condensation

(b) Sublimation

(c) Film wise condensation

(d) None

Ans: (d)

45. Steam is a

(a) Gas

(b) Vapor

(c) gas and vapor

(d) None

Ans: (b)

https://www.mesubjects.net/wp-admin/post.php?post=7493&action=edit  MCQ Entropy of steam