Home

What is the correct answer?

4

A gas shows deviation from ideal behaviour at

A. Low pressure and high temperature

B. Low pressure and low temperature

C. Low temperature and high pressure

D. High temperature and high pressure

Correct Answer :

C. Low temperature and high pressure


Related Questions

What is the correct answer?

4

The entropy change in a reversible isothermal process, when an ideal gas expands to four times its initial volume is

A. R loge 4

B. R log10 4

C. Cv log10 4

D. Cv loge 4

What is the correct answer?

4

The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

A. 100,000 kW

B. 160,000 kW

C. 200,000 kW

D. 320,000 kW

What is the correct answer?

4

For spontaneous changes in an isolated system (S = entropy)

A. ds = 0

B. ds <0

C. ds > 0

D. ds = Constant

What is the correct answer?

4

In reactions involving solids and liquids (where change in volume is negligible), the heat of reaction at constant pressure as compared to that at constant volume is

A. More

B. Less

C. Same

D. Unpredictable; depends on the particular reaction

What is the correct answer?

4

For an exothermic reaction

A. Only enthalpy change (ΔH) is negative

B. Only internal energy change (ΔE) is negative

C. Both ΔH and ΔE are negative

D. Enthalpy change is zero

What is the correct answer?

4

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

What is the correct answer?

4

Heat requirement for decomposition of a compound into its elements is __________ that is evolved during the formation of that compound from its elements.

A. The same

B. Less than

C. Greater than

D. Different than

What is the correct answer?

4

Which is not a refrigerant?

A. SO2

B. NH3

C. CCl2F2

D. C2H4Cl2

What is the correct answer?

4

What happens in a reversible adiabatic compression?

A. Heating occurs

B. Cooling occurs

C. Pressure is constant

D. Temperature is constant

What is the correct answer?

4

In which of the following reaction equilibrium, the value of equilibrium constant Kp will be more than is Kc?

A. 2HI H2 + I2

B. N2O4 2NO2

C. 2SO2 + O2 2SO3

D. None of these

What is the correct answer?

4

Fugacity is most helpful in

A. Representing actual behaviour of real gases

B. Representing actual behaviour of ideal gases

C. The study of chemical equilibria involving gases at atmospheric pressure

D. None of these

What is the correct answer?

4

The adiabatic throttling process of a perfect gas is one of constant enthalpy

A. In which there is a temperature drop

B. Which is exemplified by a non-steady flow expansion

C. Which can be performed in a pipe with a constriction

D. In which there is an increase in temperature

What is the correct answer?

4

The expression for the work done for a reversible polytropic process can be used to obtain the expression for work done for all processes, except reversible __________ process.

A. Isobaric

B. Isothermal

C. Adiabatic

D. None of these

What is the correct answer?

4

If heat contents of CH4, C2H4 and C3H8 are -17.9, 12.5 and -24.8 kcal/mole respectively, than ΔH for the reaction CH4(g) + C2H4(g) C3H8(g) will be __________ Kcal.

A. -19.4

B. -30.2

C. 55.2

D. -55.2

What is the correct answer?

4

When a system is in equilibrium for all possible processes, the differential or finite change of entropy is

A. < 0

B. > 0

C. = 0

D. None of these

What is the correct answer?

4

Heat is added at constant pressure in an ideal __________ cycle.

A. Stirling

B. Brayton

C. Rankine

D. Both (B) and (C)

What is the correct answer?

4

Critical solution temperature (or the consolute temperature) for partially miscible liquids (e.g., phenol-water) is the minimum temperature at which

A. A homogeneous solution (say of phenol water) is formed

B. Mutual solubility of the two liquids shows a decreasing trend

C. Two liquids are completely separated into two layers

D. None of these

What is the correct answer?

4

To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (ΔHV/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)

What is the correct answer?

4

Internal energy of an element at 1 atm and 25° C is __________ kcal/kg.mole.

A. 0

B. 273

C. 25

D. None of these

What is the correct answer?

4

During Joule-Thomson expansion of gases

A. Enthalpy remains constant

B. Entropy remains constant

C. Temperature remains constant

D. None of these

What is the correct answer?

4

Which of the following has the minimum value of COP for a given refrigeration effect?

A. Reverse Carnot cycle

B. Ordinary vapour-compression cycle

C. Vapour-compression process with a reversible expansion engine

D. Air refrigeration cycle

What is the correct answer?

4

The equation, Cp - Cv = R, is true for __________ gas.

A. No

B. Any real

C. Only ideal

D. Both (B) and (C)

What is the correct answer?

4

Maxwell's relation corresponding to the identity, dH = dS = Vdp + Σμi dni is

A. (∂T/∂V)S, ni = -(∂P/∂S)V, ni

B. (∂S/∂P)T, ni = (∂V/∂T)P, ni

C. (∂S/∂V)T, ni = (∂P/∂T)V, ni

D. (∂T/∂P)S, ni = (∂V/∂S)P, ni

What is the correct answer?

4

Consider the reaction, C + O2 CO2; ΔH = - 94 kcal. What will be the value of ΔH for the reaction CO2 → C + O2?

A. -94 kcal

B. +94 kcal

C. > 94 kcal

D. < -94 kcal

What is the correct answer?

4

When a gas is subjected to adiabatic expansion, it gets cooled due to

A. Decrease in velocity

B. Decrease in temperature

C. Decrease in kinetic energy

D. Energy spent in doing work

What is the correct answer?

4

As the time is passing, entropy of the universe

A. Is increasing

B. Is decreasing

C. Remain constant

D. Data insufficient, can't be predicted

What is the correct answer?

4

Which of the following will increase the volume of a real gas by four times?

A. Doubling the absolute temperature as well as pressure of the gas

B. Reducing pressure to one fourth at constant temperature

C. Reducing temperature to one fourth at constant pressure

D. Reducing the temperature to half and doubling the pressure

What is the correct answer?

4

Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture __________ calorimeter is not used for measuring the dryness fraction of steam.

A. Bomb

B. Separating

C. Bucket

D. Throttling

What is the correct answer?

4

Requisites of a reversible process is that the

A. System and surroundings pressure be equal

B. Friction in the system should be absent

C. System and surroundings temperature be equal

D. None of these

What is the correct answer?

4

The first law of thermodynamics is a restatement of the law of conservation of

A. Mass

B. Energy

C. Momentum

D. None of these