What is the value of ln y (where y = activity co-efficient) for ideal gases? (A) Zero (B) Unity (C) Infinity (D) Negative

What is the value of ln y (where y = activity co-efficient) for ideal
gases?
(A) Zero
(B) Unity
(C) Infinity
(D) Negative
by

1 Answer

Answer :

(A) Zero
by

Related questions

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 a component is equal to the partial pressure of the component. (D) The fugacity co-efficient is zero for an ideal gas

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

The reflection co-efficient at the open circuited end of a transmission line. (a) zero (b) infinity (c) unity (d) none of the above

Description : The reflection co-efficient at the open circuited end of a transmission line. (a) zero (b) infinity (c) unity (d) none of the above

Last Answer : (c) unity

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

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

For an ideal liquid solution, which of the following is unity? (A) Activity (B) Fugacity (C) Activity co-efficient (D) Fugacity co-efficient

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

The expression, nRT ln(P1/P2), is for the __________of an ideal gas. (A) Compressibility (B) Work done under adiabatic condition (C) Work done under isothermal condition (D) Co-efficient of thermal expansion

Description : The expression, nRT ln(P1/P2), is for the __________of an ideal gas. (A) Compressibility (B) Work done under adiabatic condition (C) Work done under isothermal condition (D) Co-efficient of thermal expansion

Last Answer : C) Work done under isothermal condition

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

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

Which one is true for a throttling process? (A) A gas may have more than one inversion temperatures (B) The inversion temperature is different for different gases (C) The inversion temperature is same for all gases (D) The inversion temperature is the temperature at which Joule-Thomson co-efficient is infinity

Description : Which one is true for a throttling process? (A) A gas may have more than one inversion temperatures (B) The inversion temperature is different for different gases (C) The inversion ... gases (D) The inversion temperature is the temperature at which Joule-Thomson co-efficient is infinity

Last Answer : (B) The inversion temperature is different for different gases

The conductivity in free space medium is a) Infinity b) Unity c) Zero d) Negative

Description : The conductivity in free space medium is a) Infinity b) Unity c) Zero d) Negative

Last Answer : c) Zero

As the temperature is lowered towards the absolute zero, the value of ∂(∆F)/∂T, then approaches (A) Unity (B) Zero (C) That of the heat of reaction (D) Infinity

Description : As the temperature is lowered towards the absolute zero, the value of ∂(∆F)/∂T, then approaches (A) Unity (B) Zero (C) That of the heat of reaction (D) Infinity

Last Answer : B) Zero

As the temperature is lowered towards the absolute zero, the value of the quantity (∂∆F/∂T) approaches (A) Zero (B) Unity (C) Infinity (D) None of these

Description : As the temperature is lowered towards the absolute zero, the value of the quantity (∂∆F/∂T) approaches (A) Zero (B) Unity (C) Infinity (D) None of these

Last Answer : (A) Zero

. In a shell and tube heat exchanger, the tube side heat transfer co￾efficient just at the entrance of the tube is (A) Infinity (B) Zero (C) Same as average heat transfer co-efficient for tube side (D) None of these

Description : . In a shell and tube heat exchanger, the tube side heat transfer co￾efficient just at the entrance of the tube is (A) Infinity (B) Zero (C) Same as average heat transfer co-efficient for tube side (D) None of these

Last Answer : (A) Infinity

Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is (A) Positive (B) Negative (C) Zero (D) Infinity

Description : Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is (A) Positive (B) Negative (C) Zero (D) Infinity

Last Answer : C) Zero

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

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

For an ideal solution, the value of activity co-efficient is (A) 0 (B) 1 (C) < 1 (D) > 1

Description : For an ideal solution, the value of activity co-efficient is (A) 0 (B) 1 (C) < 1 (D) > 1

Last Answer : (B) 1

While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is (A) Infinity (B) Unity (C) Constant (D) Negative

Description : While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is (A) Infinity (B) Unity (C) Constant (D) Negative

Last Answer : (C) Constant

Out of the following four assumptions used in the derivation of theequation for LMTD[LMTD = (∆t1- ∆t2)/ln(∆t1/∆t2)], which one is subject to the largest deviationin practice ?(A) Constant overall heat transfer co-efficient.(B) Constant rate of fluid flow(C) Constant specific heat(D) No partial phase change in the system

Description : Out of the following four assumptions used in the derivation of theequation for LMTD [LMTD = (∆t1 - ∆t2 )/ln(∆t1 /∆t2 )], which one is subject to the largest deviation in practice ? (A) Constant ... (B) Constant rate of fluid flow (C) Constant specific heat (D) No partial phase change in the system

Last Answer : (B) Constant rate of fluid flow

When the feed to a distillation column is a saturated liquid, slope of thefeed line is(A) Zero(B) Unity(C) Infinity(D) None of these

Description : When the feed to a distillation column is a saturated liquid, slope of thefeed line is (A) Zero (B) Unity (C) Infinity (D) None of these

Last Answer : (C) Infinity

What is the reflux ratio at total reflux? (A) Zero (B) Infinity (C) Unity

Description : What is the reflux ratio at total reflux? (A) Zero (B) Infinity (C) Unity

Last Answer : (B) Infinity

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

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

The potential difference in an open circuit is a) Zero b) Unity c) Infinity d) Circuit does not exist open

Description : The potential difference in an open circuit is a) Zero b) Unity c) Infinity d) Circuit does not exist open

Last Answer : c) Infinity

For a test charge placed at infinity, the electric field will be a) Unity b) +∞ c) Zero d) -∞

Description : For a test charge placed at infinity, the electric field will be a) Unity b) +∞ c) Zero d) -∞

Last Answer : c) Zero

What is the entropy of a pure substance at a temperature of absolute zero?  a. unity  b. zero  c. infinity  d. undefined

Description : What is the entropy of a pure substance at a temperature of absolute zero?  a. unity  b. zero  c. infinity  d. undefined

Last Answer : zero

What will be the reflection coefficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ? (a) Zero (b) Unity (c) Infinity (d) None of the above

Description : What will be the reflection coefficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ? (a) Zero (b) Unity (c) Infinity (d) None of the above

Last Answer : (a) Zero

Joule-Thomson co-efficient for a perfect gas is (A) Zero (B) Positive (C) Negative(D) None of these

Description : Joule-Thomson co-efficient for a perfect gas is (A) Zero (B) Positive (C) Negative (D) None of these

Last Answer : (A) Zero

At minimum reflux ratio for a given separation (A) Number of plates is zero (B) Number of plates is infinity (C) Minimum number of the theoretical plates is required (D) Separation is most efficient

Description : At minimum reflux ratio for a given separation (A) Number of plates is zero (B) Number of plates is infinity (C) Minimum number of the theoretical plates is required (D) Separation is most efficient

Last Answer : (B) Number of plates is infinity

Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a measure of its capacity and is equal to the residence time when the density of reaction mixture is constant (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty (D) In an ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction

Description : Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a ... ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction

Last Answer : (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty

Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B) The co-efficient of contraction of a Venturimeter is always unity (C) For a fixed pressure drop, the discharge of a gas through a Venturimeter is greater, when compressibility is taken into account, than when it is neglected (D) None of these

Description : Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B ... , when compressibility is taken into account, than when it is neglected (D) None of these

Last Answer : (D) None of these

What is the value of Joule-Thomson co-efficient for an ideal gas? (A) +ve (B) -ve (C) 0 (D) ∞

Description : What is the value of Joule-Thomson co-efficient for an ideal gas? (A) +ve (B) -ve (C) 0 (D) ∞

Last Answer : (C) 0

Specific heat of a gas for a reversible adiabatic process is (A) Negative (B) Zero (C) Infinity (D) None of these

Description : Specific heat of a gas for a reversible adiabatic process is (A) Negative (B) Zero (C) Infinity (D) None of these

Last Answer : (B) Zero

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

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

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-efficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of (A) Temperature only (B) Temperature and pressure only (C) Temperature, pressure and liquid composition xi only (D) Temperature, pressure, liquid composition xi and vapour composition yi

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

For an ideal gas, the chemical potential is given by (A) RT d ln P (B) R d ln P (C) R d ln f (D) None of these

Description : For an ideal gas, the chemical potential is given by (A) RT d ln P (B) R d ln P (C) R d ln f (D) None of these

Last Answer : (A) RT d ln P

The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for (A) Expansion of a real gas (B) Reversible isothermal volume change (C) Heating of an ideal gas (D) Cooling of a real gas

Description : The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for (A) Expansion of a real gas (B) Reversible isothermal volume change (C) Heating of an ideal gas (D) Cooling of a real gas

Last Answer : (B) Reversible isothermal volume change

The expression, ∆G = nRT. ln(P2/P1), gives the free energy change (A) With pressure changes at constant temperature (B) Under reversible isothermal volume change (C) During heating of an ideal gas (D) During cooling of an ideal gas

Description : The expression, ∆G = nRT. ln(P2/P1), gives the free energy change (A) With pressure changes at constant temperature (B) Under reversible isothermal volume change (C) During heating of an ideal gas (D) During cooling of an ideal gas

Last Answer : (A) With pressure changes at constant temperature

To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (∆HV/R) (1/T1- 1/T2) from the exact Clapeyron equation, it is assumed that the (A) Volume of the liquid phase is negligible compared to that of vapour phase (B) Vapour phase behaves as an ideal gas (C) Heat of vaporisation is independent of temperature (D) All (A), (B) & (C)

Description : To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (∆HV/R) (1/T1- 1/T2) from the exact Clapeyron equation, it is assumed that the (A) Volume of the liquid phase is negligible compared to ... gas (C) Heat of vaporisation is independent of temperature (D) All (A), (B) & (C)

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

The expression for entropy change given by, ΔS = nR ln (V2/V1) + nCvln (T2/T1) is valid for (A) Reversible isothermal volume change (B) Heating of a substance (C) Cooling of a substance (D) Simultaneous heating and expansion of an ideal gas

Description : The expression for entropy change given by, ΔS = nR ln (V2/V1) + nCvln (T2/T1) is valid for (A) Reversible isothermal volume change (B) Heating of a substance (C) Cooling of a substance (D) Simultaneous heating and expansion of an ideal gas

Last Answer : (D) Simultaneous heating and expansion of an ideal gas

Which of the following is Clausius-Clapeyron Equation for vaporisation of an ideal gas under the condition that the molar volume of liquid is negligible compared to that of the vapor? (A) d ln p/dt = Hvap/RT2 (B) d ln p/dt = RT2/Hvap (C) dp/dt = RT2/Hvap (D) dp/dt = Hvap/RT2

Description : Which of the following is Clausius-Clapeyron Equation for vaporisation of an ideal gas under the condition that the molar volume of liquid is negligible compared to that of the vapor? (A) d ln p/dt = Hvap/RT2 (B) d ln p/dt = RT2/Hvap (C) dp/dt = RT2/Hvap (D) dp/dt = Hvap/RT2

Last Answer : (A) d ln p/dt = Hvap/RT2

The focal length of a plane mirror is (1) Positive (2) Negative (3) Zero (4) Infinity

Description : The focal length of a plane mirror is (1) Positive (2) Negative (3) Zero (4) Infinity

Last Answer : (4) Infinity Explanation: A plane mirror is a mirror with a flat reflective surface. The focal length of a plane mirror is infinity. Its optical power is zero.

When temperature rises, resistance of negative temperature coefficient thermistor A. increases B. decreases C. zero D. infinity

Description : When temperature rises, resistance of negative temperature coefficient thermistor A. increases B. decreases C. zero D. infinity

Last Answer : decreases

Gravitational potential is always A. positive B. negative C. zero D. infinity

Description : Gravitational potential is always A. positive B. negative C. zero D. infinity

Last Answer : negative

The magnetic susceptibility in a superconductor will be a) Positive b) Negative c) Zero d) Infinity

Description : The magnetic susceptibility in a superconductor will be a) Positive b) Negative c) Zero d) Infinity

Last Answer : b) Negative

The potential taken between two points across a resistor will be a) Positive b) Negative c) Zero d) Infinity

Description : The potential taken between two points across a resistor will be a) Positive b) Negative c) Zero d) Infinity

Last Answer : b) Negative

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

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

Pick out the wrong statement. (A) In solvent extraction, the distribution co-efficient should be as large as possible for solvent economy (B) With increase in pressure, the solubility of gases in solvent increases at a fixed temperature (C) Decrease in Murphree plate efficiency is an indication of entrainment in distillation column (D) The capacity of a distillation column is maximum at total reflux

Description : Pick out the wrong statement. (A) In solvent extraction, the distribution co-efficient should be as large as possible for solvent economy (B) With increase in pressure, the solubility of ... in distillation column (D) The capacity of a distillation column is maximum at total reflux

Last Answer : (D) The capacity of a distillation column is maximum at total reflux

The film co-efficient is decreased due to the presence of non-condensing gases in the vapors. The film co-efficient of superheated vapor as compared to that of saturated vapor is (A) More (B) Less (C) Some (D) Either more or less; depends on the nature of vapor

Description : The film co-efficient is decreased due to the presence of non-condensing gases in the vapors. The film co-efficient of superheated vapor as compared to that of saturated vapor is (A) More (B) Less (C) Some (D) Either more or less; depends on the nature of vapor

Last Answer : (C) Some

When the voltage and the current developed in an AC circuit reach their peak values at the same time, the power factor is considered to be _____________. A. lagging B. leading C. unity D. infinity

Description : When the voltage and the current developed in an AC circuit reach their peak values at the same time, the power factor is considered to be _____________. A. lagging B. leading C. unity D. infinity

Last Answer : Answer: C

the exit gradient in the absence of a downstream cut-off is (A) 0 (B) Unity (C) Infinity (D) Very large

Description : the exit gradient in the absence of a downstream cut-off is (A) 0 (B) Unity (C) Infinity (D) Very large

Last Answer : Answer: Option C

The transfer function of a system is 10/(1+s) when operating as a unity feedback system, the steady state error to a step input will be a) 0 b) 1/11 c) 10 d) Infinity

Description : The transfer function of a system is 10/(1+s) when operating as a unity feedback system, the steady state error to a step input will be a) 0 b) 1/11 c) 10 d) Infinity

Last Answer : Ans: 1/11

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

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