Description : Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature. (A) Decreases (B) Increases (C) Remains constant
Last Answer : (B) Increases
Description : Which of the following is not affected by temperature changes? (A) Fugacity (B) Activity co-efficient (C) Free energy (D) None of these
Last Answer : (D) None of these
Description : Gibbs-Duhem equation relates composition in liquid phase and the __________ at constant temperature & pressure. (A) Fugacity (B) Partial pressure (C) Activity co-efficient (D) All (A), (B), and (C)
Last Answer : (D) All (A), (B), and (C)
Description : Partial molar free energy of an element A in solution is same as its (A) Chemical potential (B) Activity (C) Fugacity (D) Activity co-efficient
Last Answer : (A) Chemical potential
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 : For an ideal liquid solution, which of the following is unity? (A) Activity (B) Fugacity (C) Activity co-efficient (D) Fugacity co-efficient
Last Answer : (C) Activity co-efficient
Description : Pick out the wrong statement. (A) Activity co-efficient is dimensionless. (B) In case of an ideal gas, the fugacity is equal to its pressure. (C) In a mixture of ideal gases, the fugacity of ... equal to the partial pressure of the component. (D) The fugacity co-efficient is zero for an ideal gas
Last Answer : (D) The fugacity co-efficient is zero for an ideal gas
Description : With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure (A) Increases (B) Decreases (C) Remain same (D) Decreases linearly
Last Answer : (A) Increases
Description : The standard state of a gas (at a given temperature) is the state in which fugacity is equal to (A) Unity (B) Activity (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : For a given substance at a specified temperature, activity is __________ to fugacity. (A) Directly proportional (B) Inversely proportional (C) Equal (D) None of these
Last Answer : (A) Directly proportional
Description : In an ideal solution, the activity of a component equals its (A) Mole fraction (B) Fugacity at the same temperature and pressure (C) Partial pressure (D) None of these
Last Answer : (A) Mole fraction
Description : The molar excess Gibbs free energy, gE, for a binary liquid mixture at T and P is given by, (gE/RT) = A . x1. x2, where A is a constant. The corresponding equation for ln y1, where y1is the activity co-efficient of component 1, is (A) A . x22 (B) Ax1 (C) Ax2 (D) Ax12
Last Answer : (A) A . x22
Description : Convective heat transfer co-efficient in case of fluid flowing in tubes is not affected by the tube length/diameter ratio, if the flow is in the __________ zone. (A) Laminar (B) Transition (C) Both 'a' & 'b' (D) Highly turbulent
Last Answer : (D) Highly turbulent
Description : Mass transfer co-efficient of liquid is (A) Affected more by temperature than that for gases (B) Affected much less by temperature than that for gases
Last Answer : (A) Affected more by temperature than that for gases
Description : ________ Equation predicts the activity co-efficient from experimental data. (A) Lewis-Randall (B) Margules (C) Van Laar (D) Both (B) & (C)
Last Answer : (D) Both (B) & (C)
Description : In a homogeneous solution, the activity co-efficient of a component depends upon the (A) Pressure (B) Composition (C) Temperature (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Pick out the wrong statement. (A) Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C ... in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & prod
Last Answer : (C) Enzymes help in increasing the activation energy of the reaction
Description : In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient (A) Increases (B) Decreases (C) Is not affected (D) May increase or decrease; depends on the feed
Last Answer : (B) Decreases
Description : What is the value of ln y (where y = activity co-efficient) for ideal gases? (A) Zero (B) Unity (C) Infinity (D) Negative
Last Answer : (A) Zero
Description : For an ideal solution, the value of activity co-efficient is (A) 0 (B) 1 (C) < 1 (D) > 1
Last Answer : (B) 1
Description : At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole ... respectively. Activity co-efficient of methanol is (A) 1.572 (B) 1.9398 (C) 3.389
Last Answer : (A) 1.572
Description : For an ideal gas, the activity co-efficient is (A) Directly proportional to pressure (B) Inversely proportional to pressure (C) Unity at all pressures (D) None of these
Last Answer : (C) Unity at all pressures
Description : Which of the following equations is used for the prediction of activity co-efficient from experiments? (A) Van Laar equation (B) Margules equation (C) Wilson's equation (D) All (A), (B) and (C)
Description : Activity co-efficient is a measure of the (A) Departure from ideal solution behaviour (B) Departure of gas phase from ideal gas law (C) Vapour pressure of liquid (D) None of these
Last Answer : (A) Departure from ideal solution behaviour
Description : The activity co-efficient of the solute in a dilute solution (A) Decreases with the increase of concentration of the solute (B) Increases with the increase of concentration of the solute (C) Remains constant (D) Is unity at infinite dilution
Last Answer : (C) Remains constant
Description : Dephosphorization of molten pig iron is favoured by (A) Oxidising and basic slag (B) Reducing and basic slag (C) High activity co-efficient of phosphorous in metal (D) Oxidising and neutral slag
Last Answer : Option B
Description : Fugacity of a component in an ideal gas mixture is equal to the partial pressure of that component in the mixture. The fugacity of each component in a stable homogeneous solution at constant pressure and ... increases. (A) Decreases (B) Decreases exponentially (C) Increases (D) Remain constant
Last Answer : (C) Increases
Description : The unit of fugacity is the same as that of the (A) Pressure (B) Temperature (C) Volume (D) Molar concentration
Last Answer : (A) Pressure
Description : For multi-component multiple phases to be in equilibrium at the same pressure and temperature, the __________ of each component must be same in all phases. (A) Chemical potential (B) Fugacity (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : For a stable phase at constant pressure and temperature, the fugacity of each component in a binary system __________ as its mole fraction increases. (A) Decreases (B) Increases (C) Remain same (D) Decreases linearly
Description : In a homogeneous solution, the fugacity of a component depends upon the (A) Pressure (B) Composition (C) Temperature (D) All (A), (B) and (C)
Description : Fugacity and pressure are numerically not equal for the gases (A) At low temperature and high pressure (B) At standard state (C) Both (A) and (B) (D) In ideal state
Description : Fugacity and pressure are numerically equal, when the gas is (A) In standard state (B) At high pressure (C) At low temperature (D) In ideal state
Last Answer : (D) In ideal state
Description : Gaseous diffusion co-efficient increases with increase in the (A) Pressure (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Temperature
Description : Diffusion co-efficient generally depends upon the temperature, pressure & the nature of the components of the system. Its dimension is not the same as that of the (A) Mass transfer co-efficient (B) Thermal diffusivity (C) Kinematic viscosity (D) Volumetric diffusivity
Last Answer : (A) Mass transfer co-efficient
Description : Joule-Thomson co-efficient depends on the (A) Pressure (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : A thin, flat & square plate measuring 2 m 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will ... heat transfer co-efficient is __________ W/m2 °C. (A) 50 (B) 100 (C) 150 (D) 200
Last Answer : (B) 100
Description : Diffusion co-efficient of a metal in a solid solution depends upon its (A) Composition (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : An ideal coolant for a nuclear reactor should (A) Be a good absorber of neutrons (B) Be capable of attaining high temperature, only when it is pressurised (C) Have high density, but low heat transfer co-efficient (D) Be free from radiation damage and non-corrosive
Last Answer : (D) Be free from radiation damage and non-corrosive
Description : At equilibrium condition, the chemical potential of a material in different phases in contact with each other is equal. The chemical potential for a real gas (μ) is given by (where, μ = standard chemical potential at unit fugacity (f° = 1 atm. ... (B) μ°+ R ln f (C) μ° + T ln f (D) μ° + R/T ln f
Last Answer : (A) μ° + RT ln f
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 : For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be (A) 6738.9 (B) 6753.5 (C) 7058.3 (D) 9000
Last Answer : (B) 6753.5
Description : Fugacity is a measure of the (A) Escaping tendencies of the same substance in different phases of a system (B) Relative volatility of a mixture of two miscible liquids (C) Behaviour of ideal gases (D) None of these
Last Answer : (A) Escaping tendencies of the same substance in different phases of a system
Description : “The fugacity of a gas in a mixture is equal to the product of its mole fraction and its fugacity in the pure state at the total pressure of the mixture". This is (A) The statement as per Gibbs-Helmholtz (B) Called Lewis-Randall rule (C) Henry's law (D) None of these
Last Answer : (B) Called Lewis-Randall rule
Description : . Which of the following relationships between co-efficient of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct? (A) μ > tan α (B) μ ≥ tan α (C) μ > tan 2α (D) μ ≤ tan α
Last Answer : (B) μ ≥ tan α
Description : Babbitt metal used for making bearings should have (A) High co-efficient of friction between journal and bearing (B) Ability to retain lubricant on its surface (C) Low co-efficient of friction between journal and bearing (D) Both (B) & (C)
Last Answer : (A) High co-efficient of friction between journal and bearing
Description : Pick out the wrong statement. (A) 'Solvates' are chemical compounds formed by solute with their solvents. When water is the solvent, then it is called a 'hydrate' (B) In heat exchanger ... vertical evaporators, area of central downtake is about 50 to 100% of the total tube cross-sectional area
Last Answer : (C) Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted
Description : A coal with high ash content is undesirable, as (A) It is abrasive to the coal pulveriser (i.e. ball mill) and the combustion chamber (B) The ash in molten condition gets absorbed in the pores of the ... and stick to the boiler tubes thereby reducing the heat transfer (D) All (A), (B) and (C)
Description : Which of the following is an undesirable property of a manometricliquid? (A) Non-sticky & non-corrosive nature (B) High vapour pressure (C) Low viscosity & surface tension (D) Low co-efficient of thermal expansion
Last Answer : (B) High vapour pressure
Description : The discharge co-efficient for an orifice meter does not depend upon the (A) Pipe length (B) Ratio of pipe diameter to orifice diameter (C) Type of orifice & the Reynolds number (D) Pipe diameter
Last Answer : (A) Pipe length