Work done in the reversible adiabatic process is given by:

1. 2.303 RT log (V₂/V₁)                     

2. $\frac{\mathrm{nR}<mspace\; width="1em"></mspace>}{(\mathrm{\gamma }-1)}({\mathrm{T}}_2-{\mathrm{T}}_1)$

3. 2.303 RT log(V₁/V₂)                     

4. none of these

The work done by a mass less piston in causing an expansion $∆$V (at constant temperature), when the opposing pressure, P is variable, is given by:

1. W= $-\int \mathrm{P}∆\mathrm{V}$               

2. W=0

3. W= -P$∆$V                     

4. none of these

The maximum work done in expanding 16 g of oxygen at 300 K and occupying a volume of 5 dm³ isothermally until the volume becomes 25 dm³ is:

1. -2.01 x 10³ J                       

2. 2.81 x 10³ J

3. 2.01 x 10^-3 J                     

4. -2.01 x 10^-6 J

 During an adiabatic process:

1. pressure is maintained constant

2. gas is isothermally expanded

3. there is perfect heat insulation

4. the system changes heat with surroundings

The internal energy change when a system goes from state A to B is 40 kJ/mol. If the system goes from A to B by a reversible path and returns to state A by an irreversible path. What would be the change in internal energy?

1. 40 kJ                                   

2. >40 kJ

3. <40 kJ                                 

4. Zero

The mathematical form of the first law of thermodynamics when heat (q) is supplied and W is work done by the system (-ve) is:

1. $∆$U=q+W                       

2. $∆$U=q-W

3. $∆$U=-q+W                       

4. $∆$U= -q-W

5 moles of an ideal gas expands isothermally and irreversibly from a pressure of 10 atm to 1 atm against a constant external pressure of 1 atm. find the W_irr at 300 K:-

1. -15.921 kJ

2. -11.224 kJ

3. -110.83 kJ

4. None of these

Consider the reactionat 300K

H₂₍₉₎ + Cl₂₍₉₎ →2HCI_(g), ΔH° = — 185 KJ

If 3 mole of H₂ completely react with 3 mol of Cl₂ to form Cl, $∆$U° of the reaction will be

(1) Zero

(2) –185 KJ

(3) -555 KJ

(4) None

An ideal gas is taken from the same initial pressure P₁ to the same final pressure P₂ by three different processes. If it is known that point 1 corresponds to a reversible adiabatic and point 2 corresponds to a single stage adiabatic then

(1) Point 3 may be a two stage adiabatic.

(2) the average K.E. of the gas is maximum at point 1

(3) Work done by surrounding in reaching point number '3' will be maximum

(4) If point4 and point 5 lie along a reversible isotherm then T₅ < T₁.

Which of the following best describes the behavior of an ideal gas during isothermal expansion?
(ΔE & ΔH represent the change in internal energy and enthalpy respectively)

1. ΔE and ΔH increases

2. ΔE increases but ΔH decreases

3. ΔE decreases but ΔH increases

4. ΔE = 0 and ΔH = 0