Gibbs free energy per mole for a pure substance is equal to the (A) Latent heat of vaporisation
(B) Chemical potential
(C) Molal boiling point
(D) Heat capacity

1 Answer

Answer :

(B) Chemical potential

Related questions

Description : The chemical potential for a pure substance is __________ its partial molal free energy. (A) More than (B) Less than (C) Equal to (D) Not related to

Last Answer : (C) Equal to

Description : Specific/molar Gibbs free energy for a pure substance does not change during (A) Sublimation (B) Vaporisation (C) Melting (D) Either (A), (B) or (C)

Last Answer : (D) Either (A), (B) or (C)

Description : The change in Gibbs free energy for vaporisation of a pure substance is (A) Positive (B) Negative (C) Zero (D) May be positive or negative

Last Answer : (C) Zero

Description : It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of ... 3.06 10 5 (B) 6.12 10 5 (C) 7.24 10 5 (D) 9.08 10

Last Answer : (A) 3.06 × 10

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 : At constant temperature and pressure, for one mole of a pure substance, the ratio of the free energy to the chemical potential is (A) Zero (B) One (C) Infinity (D) Negative

Last Answer : (B) One

Description : Entrainer used in Azeotropic distillation should (A) Form a low boiling azeotrope with one of the constituents of the mixture (B) Form a new azeotrope of low relative volatility with one of the ... (C) Have high latent heat of vaporisation (D) Have high viscosity to provide high tray efficiency

Last Answer : (A) Form a low boiling azeotrope with one of the constituents of the mixture

Description : Calculate the enthalpy of vaporisation per mole for ethanol. Given `DeltaS = 109.8 J K^(-1) mol^(-1)` and boiling point of ethanol is `78.5^(@)`.

Last Answer : Calculate the enthalpy of vaporisation per mole for ethanol. Given `DeltaS = 109.8 J K^(-1) mol^(-1)` ... KJ mol^(-1)` D. Some more data is required

Description : What is the heat capacity of one mole of substance?  A. Molecular heat  B. Specific heat  C. Latent heat  D. Molar heat

Last Answer : Molar heat

Description : At normal boiling point, molar entropy of vaporisation is __________ Joule/K°.mole. (A) 72 (B) 92 (C) 142 (D) 192

Last Answer : (B) 92

Description : Steam at 1000C causes more severe burns than water at 100° C because (1) steam has no specific heat capacity (2) steam has latent heat of vaporisation (3) water has no specific heat capacity (4) water has latent heat of fusion

Last Answer :  steam has latent heat of vaporisation

Description : Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.). (A) Entropy (B) Internal energy (C) Enthalpy (D) Gibbs free energy

Last Answer : (D) Gibbs free energy

Description : _________ does not change during phase transformation processes like sublimation, melting & vaporisation. (A) Entropy (B) Gibbs free energy (C) Internal energy (D) All (A), (B) & (C)

Last Answer : (B) Gibbs free energy

Description : Chemical potential (an intensive property) of a substance is a force that drives the chemical system to equilibrium and is equal to its partial molar properties. The ratio of chemical potential to free energy of a pure substance ... temperature and pressure is (A) 0 (B) 1 (C) ∞ (D) None of these

Last Answer : (B) 1

Description : When the solvent dissolves very little of solute, then (A) Solvent of low latent heat of vaporisation should be used (B) Solvent of low freezing point should be used (C) Large quantity of solvent is required to extract the solute (D) Very small quantity of solvent is required

Last Answer : (C) Large quantity of solvent is required to extract the solute

Description : ick out the undesirable property for a good refrigerant. (A) High thermal conductivity (B) Low freezing point (C) Large latent heat of vaporisation (D) High viscosity

Last Answer : (D) High viscosity

Description : Water is not suitable as a calorimetric substance because it – (1) has high specific heat (2) is a good conductor (3) has high boiling point (4) low latent heat of vaporization

Last Answer : (1) has high specific heat Explanation: The specific heat of water is higher than all other common substances. Hence, water is used for heating purposes (as in hot water bottles) and for cooling ... the liquids, mercury has the lowest specific heat due to which it is used as a thermometric liquid.

Description : Water is not suitable as a calorimetric substance because it : (1) has high specific heat (2) is a good conductor (3) has high boiling point (4) low latent heat of vapourization

Last Answer : has high specific heat

Description : For a multi-component system, the term chemical potential is equivalent to the (A) Molal concentration difference (B) Molar free energy (C) Partial molar free energy (D) Molar free energy change

Last Answer : (C) Partial molar free energy

Description : Which of the following assumes constant molal vaporisation and overflow? (A) McCabe-Thiele method (B) Ponchan-Savarit method (C) Enthalpy concentration method (D) Plate absorption column

Last Answer : (A) McCabe-Thiele method

Description : Humidity chart is useful for the solution of problems concerning condensation, vaporisation and air conditioning. At a given dry bulb temperature, value of humidity obtained from the humidity chart directly, is in ... (A) Molal (B) Relative (C) Percentage (D) None of these

Last Answer : (A) Mola

Description : The heat Q per unit mass per degree change in temperature that must be supplied or removed to change the temperature of a substance.  a. Specific Heat Capacity  b. Latent Heat  c. Heat of Transformation  d. Internal Heat

Last Answer : Specific Heat Capacity

Description : In distillation column design, the McCabe-Thiele procedure is inadequate and a Ponchan-Savarit procedure is needed, when (A) Saturated feed is not used (B) An azeotrope forms (C) The latent ... vaporisation of the more and less volatile components are greatly different (D) A total condenser is used

Last Answer : (D) A total condenser is used

Description : Heat sensitive materials with very high latent heat of vaporisation may be economically separated using (A) Liquid extraction (B) Distillation (C) Evaporation (D) Absorption

Last Answer : (A) Liquid extraction

Description : The solvent used in liquid extraction should not have high latent heat of vaporisation, because (A) The pressure drop and hence the pumping cost will be very high (B) It cannot ... by distillation may be prohibitively high (D) It will decompose while recovering by distillation

Last Answer : (C) Its recovery cost by distillation may be prohibitively high

Description : An equipment which converts the latent or sensible heat of one fluid into the latent heat of vaporisation of another, is called a (A) Boiler (B) Heat exchanger (C) Recuperator (D) Regenerato

Last Answer : (B) Heat exchanger

Description : In a cooling tower, water becomes cool by (A) Loosing sensible heat (B) Heat transfer to surroundings (C) Vaporisation due to heat loss to air (D) Loosing latent heat

Last Answer : (A) Loosing sensible heat

Description : Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of ... is negligible compared with that in the vapour state (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : High __________ is an undesirable property for a good refrigerant. (A) Specific heat (B) Latent heat of vaporisation (C) Viscosity (D) Specific vapor volume

Last Answer : (C) Viscosity

Description : The critical pressure at which the latent heat of vaporisation of steam becomes zero is __________ Kg/cm2. (A) 273.15 (B) 225.65 (C) 100.03 (D) 373.15

Last Answer : (B) 225.65

Description : What is defined as the energy required to raise the temperature of a unit mass of a substance by one degree?  A. Latent heat of fusion  B. Molar heat  C. Specific heat capacity  D. Specific heat

Last Answer : Specific heat

Description : Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than ... in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation

Last Answer : (B) Thermal conductivity of a dry material is more than that of the damp material

Description : Why high latent heat of vaporisation is desirable in a refrigerant ?

Last Answer : A high latent heat of vaporisation of refrigerant results in small amount of refrigerant and thus lesser circulation system of refrigerant for same tonnage.

Description : Pick out the wrong statement. (A) Cp of monatomic gases such as metallic vapor is about 5 kcal/kg.atom (B) The heat capacity of solid inorganic substance is exactly equal to the ... isolated system (D) At absolute zero temperature, the heat capacity for many pure crystalline substances is zero

Last Answer : (C) There is an increase in entropy, when a spontaneous change occurs in an isolated system

Description : Boiling of liquid is accompanied with increase in the (A) Vapor pressure (B) Specific Gibbs free energy (C) Specific entropy (D) All (A), (B) and (C)

Last Answer : (A) Vapor pressure

Description : Gibbs free energy of a pure fluid approaches __________ as the pressure tends to zero at constant temperature. (A) Infinity (B) Minus infinity (C) Zero (D) None of these

Last Answer : (B) Minus infinity

Description : The ______ of a substance is the amount of heat that must be added or removed from a unit mass of the substance to change its temperature by one degree.  A. Latent heat of fusion  B. Molar heat  C. Specific heat capacity  D. Specific heat

Last Answer : Specific heat capacity

Description : What is the heat capacity of one gram of a substance?  A. Molecular heat  B. Specific heat  C. Latent heat  D. Molar heat

Last Answer : Specific heat

Description : The quantity of heat required to raise the temperature of a given substance by 1 oC is known as: a) sensible heat b) specific heat c) heat capacity d) latent heat

Last Answer : specific heat specific heat is the quantity of heat required to raise the temperature of 1 gram substance by 1 oC is

Description : The chemical potential of a component (μi) of a phase is the amount by which its capacity for doing all work, barring work of expansion is increased per unit amount of substance added for an infinitesimal addition at constant temperature and ... , nj (C) (∂H/∂ni)S, P, nj (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : The amount of heat energy per kilogram that must be added or removed when a substance changes from one phase to another.  a. specific heat  b. heat of expansion  c. latent heat  d. useful heat

Last Answer : latent heat

Description : Which of the following is an extensive property of a system? (A) Heat capacity (B) Molal heat capacity (C) Pressure (D) Concentration

Last Answer : A) Heat capacity

Description : 1.0 molal aqueous solution of an electrolyte `"A"_(2)"B"_(3)` is 60% ionised. The boiling point of the solution at 1 atm is `("K"_("b"("H"_(2)"O"))=0.

Last Answer : 1.0 molal aqueous solution of an electrolyte `"A"_(2)"B"_(3)` is 60% ionised. The boiling point of the solution at ... C. `376. 4 K` D. ` 374 . 76 K`

Description : Which of the following aqueous solutions would hav the lowest boiling point? Would it be a 1.0 molal solution of: w) Hydrochloric acid x) Sodium Hydroxide y) Acetic Acid, z) Magnesium Chloride

Last Answer : ANSWER: Y -- ACETIC ACID

Description : With rise of boiling point of a water, what will be the latent heat of steam? -Do You Know?

Last Answer : answer:

Description : Choose the correct statement (a) A refrigerant should have low latent heat (b) If operating temperature of system is low, then refrigerant with low boiling point should be used (c) Pre-cooling and sub-cooling bf refrigerant are same (d) Superheat and sensible heat of a. refrigerant are same

Last Answer : Ans: b

Description : Which of the following is not a desirable property of a refrigerant (a) highmisibility with oil (b) low boiling point (c) good electrical conductor (d) large latent heat

Last Answer : Ans: c

Description : Vegetables are cooked in lesser time by adding a pinch of salt while cooking because (1) boiling point of water increases (2) latent heat of vaporization of water decreases (3) latent heat of vaporization of water increases (4) boiling point of water decreases

Last Answer : (1) boiling point of water increases Explanation: Adding salt raises the boiling point of water, which allows food to cook at higher temperature. The higher the temperature, the higher the rate of heat transfer between the food and water, thus it cooks more quickly.

Description : With rise of boiling point of a water, what will be the latent heat of steam?

Last Answer : Decreases