The dew point of an unsaturated gas-vapor mixture does not depend
upon the __________ of the mixture.
(A) Composition
(B) Temperature
(C) Total pressure
(D) All (A), (B) and (C)
Description : With increase in absolute humidity, the dew point of an unsaturated mixture of air and water vapor (at constant pressure and temperature). (A) Increases (B) Remains unchanged (C) Decreases (D) Decreases linearly
Last Answer : (A) Increases
Description : __________ is the temperature at which a gas-vapor mixture becomes saturated, when cooled at constant total pressure out of contact with a liquid. (A) Dew point (B) Bubble point (C) Dry bulb temperature (D) Wet bulb temperature
Last Answer : (A) Dew point
Description : In case of an unsaturated mixture of gas and vapor, the percentage saturation is __________ its relative saturation. (A) Lower than (B) Higher than (C) Equal to (D) Either (A) or (B), depends on the mixture composition
Last Answer : (A) Lower than
Description : The relative saturation of an unsaturated mixture of gas and vapor is independent of the (A) Nature of the vapor (B) Temperature of the mixture (C) Composition of the mixture (D) None of these
Last Answer : (D) None of these
Description : Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation
Last Answer : (B) Wet-bulb
Description : Dew point of an air-water vapor mixture (A) Decreases with decrease in pressure (B) At constant humidity & total pressure is fixed (C) Corresponding to any point on the humidity chart is obtained by projecting a ... to the temperature axis and to the saturation curve (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : __________ temperature is the steady state temperature attained by a small amount of liquid evaporating into a large quantity of unsaturated gasvapor mixture. (A) Dry bulb (B) Wet bulb (C) Dew point (D) None of these
Last Answer : (B) Wet bulb
Description : Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure ... & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure
Last Answer : (D) Relative saturation of unsaturated mixture of water vapor & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure
Description : At a fixed pressure, the humidity depends upon the partial pressure of vapor in the mixture. Humidity of a vapour free gas is __________ percent. (A) 100 (B) 0 (C) 50 (D) Between 0 and 100
Last Answer : (B) 0
Description : Dry bulb temperature of unsaturated air is more than its __________ temperature. (A) Dew point (B) Wet bulb (C) Both 'a' & 'b' (D) Neither 'a' nor 'b
Last Answer : (C) Both 'a' & 'b
Description : __________ temperature remains constant during adiabatic saturation process of unsaturated air. (A) Dew point (B) Dry bulb (C) Wet bulb (D) None of these
Last Answer : (C) Wet bulb
Description : During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains ... pressure of water vapor (C) Relative humidity (D) None of these
Last Answer : (A) Wet bulb temperature
Description : An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively ... air is: (A) 0.048 (B) 0.079 (C) 0.122 (D) 0.152
Last Answer : (D) 0.152
Description : In an operating distillation column, the (A) Vapors and liquids are at their dew point and bubble point respectively (B) Driving force for the liquid flow is its specific weight (C) Driving force for ... bottom to the top of the column (D) Highest temperature is encountered at the top of the column
Last Answer : (C) Driving force for the vapor flow is the pressure drop, as the pressure decreases gradually from the bottom to the top of the column
Description : The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature. (A) Dew point (B) Wet bulb (C) Dry bulb (D) None of these
Description : Dew point of a gas-vapour mixture (A) Increases with temperature rise (B) Decreases with temperature rise (C) Decreases with decrease in pressure (D) Increases with increase in pressure
Last Answer : (C) Decreases with decrease in pressure
Description : Which of the following parameters remains almost constant during adiabatic saturation of unsaturated air? (A) Dry bulb temperature (B) Dew point (C) Wet bulb temperature (D) None of these
Last Answer : (C) Wet bulb temperature
Description : Unsaturated air (with dry bulb temperature and dew point being 35°C and 18°C respectively) is passed through a water spray chamber maintained at 15°C. The air will be cooled (A) And ... (C) At the same relative humidity (D) And dehumidified with decrease in wet bulb temperature
Last Answer : (D) And dehumidified with decrease in wet bulb temperature
Description : In case of unsaturated air (A) Dew point < wet bulb temperature (B) Wet bulb temperature < dry bulb temperature (C) Both (A) and (B) (D) Neither (A) not (B)
Last Answer : (C) Both (A) and (B)
Description : In case of an ideal solution, the total vapor pressure varies __________ with the composition expressed as mole fraction, (A) Inversely (B) Linearly (C) Exponentially (D) None of these
Last Answer : (B) Linearly
Description : The dew point temperature is less than the wet bulb temperature for A. saturated air B. unsaturated air C. both saturated and unsaturated air D. none of the above
Last Answer : ANSWER : B
Description : Is define as the ratio of the actual pressure of the vapor a. Relative Humidity b. Humidity Ratio c. Dew Point d. Adiabatic Saturation
Last Answer : Relative Humidity
Description : The equilibrium liquid composition compared to the vapor composition in case of Azeotropic mixture is (A) More (B) Less (C) Same (D) Either more or less; depends on the system
Last Answer : (C) Same
Description : Extensive properties of a thermodynamic system depend upon the __________ of the system. (A) Specific volume (B) Temperature (C) Mass (D) Pressure
Last Answer : (C) Mass
Description : Dew point can be best defined as the: a. Absolute temperature at which air, upon heating, will evaporate moisture b. . Percentage of moisture that air can hold at a given temperature ... to condense should the temperature drop further e. . Atmospheric pressure at which air will condense moisture
Last Answer : Answer: D
Description : A 0.064 kg of octane vapor (MW = 114) is mixed with0.91 kg of air (MW = 29.0) in the manifold of an Engine. The total pressure in the manifold is 86.1 kPa, and a temperature is 290 K. assume octane behaves ideally. What is ... of the air in the mixture in KPa? a. 46.8 b. 48.6 c. 84.6 d. 64.8
Last Answer : 84.6
Description : A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around __________ °C. (A) 21.7 (B) 20 (C) 27.3 (D) 18.7
Last Answer : (D) 18.7
Description : A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is φi yi P = Yi xifi° where, Φ is a vapor fugacity component, Yiis the liquid activity co- ... and liquid composition xi only (D) Temperature, pressure, liquid composition xi and vapour composition yi
Last Answer : (C) Temperature, pressure and liquid composition xi only
Description : Cvfor an ideal gas (A) Does not depend upon temperature (B) Is independent of pressure only (C) Is independent of volume only (D) Is independent of both pressure and volume
Last Answer : (D) Is independent of both pressure and volume
Description : The heat capacities for the ideal gas state depend upon the (A) Pressure (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Temperature
Description : Pitch creosote mixture (PCM) as compared to furnace oil is a better fuel, because its (A) Emissivity factor is higher (B) Sulphur content is lower (C) Flue gas has lower dew point thereby facilitating more waste heat recovery (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : The partial molar enthalpy of a component in an ideal binary gas mixture of composition Z, at a temperature T and pressure P, is a function only of (A) T (B) T and P (C) T, P and Z (D) T and Z
Last Answer : (B) T and P
Description : When dry bulb temperature & wet bulb temperature of moist air is the same, it means that the (A) Partial pressure of water vapour is less than the total pressure (B) Humidity is < 100% & dew ... Dew point temperature of air has not reached & air is not saturated fully (D) Air is fully saturated
Last Answer : (D) Air is fully saturated
Description : The dew point of a saturated gas phase equals the __________ temperature. (A) Gas (B) Room (C) Wet bulb (D) None of these
Last Answer : (A) Gas
Description : Acid dew point temperature (ADT) of a flue gas produced by the combustion of a fuel containing 1% sulphur may be about __________ °C. (A) 80 (B) 130 (C) 180 (D) 250
Last Answer : (B) 130
Description : Psychrometry deals with the properties of gas-vapor mixture. Humidity can be determined by the measurement of the __________ of a fibre. (A) Electrical resistance (B) Thermal conductivity (C) Strength (D) None of these
Last Answer : (A) Electrical resistance
Description : In an ideal gas mixture, fugacity of a species is equal to its (A) Vapor pressure (B) Partial pressure (C) Chemical potential (D) None of these
Last Answer : (B) Partial pressure
Description : A Mixture of dry air and water,the formation of fog starts when, A. air temperature is equal to the dew point temperature B. air temperature is greater than the dew point temperature C. both a. and b. D. none of the above
Last Answer : ANSWER : A
Description : What is the temperature at which the water vapour in the mixture of water vapour in air, starts condensing called? A. condensation temperature B. dew point temperature C. vaporization temperature D. all of the above
Description : An indication of sensible heat content in air-water vapour mixture is a) wet bulb temperature b) dew point temperature c) density of air d) dry bulb temperature
Last Answer : d) dry bulb temperature
Description : The relative saturation of a partially saturated mixture of vapour and gas can be increased by __________ of the mixture. (A) Reducing the total pressure (B) Increasing the total pressure (C) Reducing the temperature (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : The binary diffusivity in gases does not depend upon the (A) Pressure (B) Temperature (C) Nature of the components (D) None of these
Description : Heat transfer rate to the charge/stock in a furnace does not depend upon the (A) Type of fuels viz. solid, liquid or gaseous (B) Flue gas temperature (C) Emissivity of refractory walls (D) Initial temperature of the charged stock
Last Answer : (A) Type of fuels viz. solid, liquid or gaseous
Description : When an unsaturated air-water mixture is heated at constant pressure, then (A) The partial pressure of water vapour increases (B) The specific humidity decreases (C) The relative humidity increases (D) The relative humidity decreases
Last Answer : D) The relative humidity decreases
Description : The difference of wet bulb temperature and adiabatic saturation temperature of unsaturated mixture of any system is (A) +ve (B) -ve (C) Zero (D) None of these
Last Answer : (A) +ve
Description : Pick out the wrong statement. (A) The mole fraction of solute is directly proportional to the molality of a 'dilute' solution (B) For a non-reacting binary mixture of ideal gases, the partial ... at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1
Last Answer : (C) Azeotropes obey Raoult's law at all temperature
Description : Pick out the wrong statement. (A) Constant pressure distillation cannot separate an Azeotropic mixture (B) Relative volatility of a binary mixture changes appreciably with the minor change in ... unity (D) Flash distillation is practised on wide spread scale in petroleum refinery
Last Answer : (B) Relative volatility of a binary mixture changes appreciably with the minor change in temperature
Description : For __________ drying, the effects of velocity, temperature and humidity of the gas and the thickness of the solid are the same. (A) Unsaturated surface (B) Constant rate (C) Both (A) and (B) (D) Neither (A) nor (B)
Description : With increase in the time of carbonisation at a particular temperature(say 1000°C), the __________ percentage in coke oven gas increases. (A) Hydrogen (B) Methane (C) Unsaturated hydrocarbons (D) All (A), (B) and (C)
Last Answer : (A) Hydrogen
Description : Chemical reaction rate of a component depends upon the (A) Composition of the component only (B) Temperature of the system (C) Pressure of the system (D) All (A), (B) and (C)