Which of the following expressions is true

1.  ΔfHθ(CO, g)=1/2ΔfHθ(CO2, g)

2.  ΔfHθ(CO, g)=ΔfHθ(C,graphite)+ 1/2 ΔfHθ (O2,g)

3.  ΔfHθ(CO, g)=ΔfHθ (CO2, g) - 1/2 ΔfHθ (O2,g)

4.  ΔfHθ(CO, g)=ΔcombHθ(C,graphite)- ΔcombHθ(CO, g)

4

ΔfHθ(CO, g)=ΔcombHθ(C,graphite)- ΔcombHθ(CO, g)

Explanation :
No Explanation available for this question

For a spontaneous endothermic reaction

1.  ΔG > 0

2.  ΔG = 0

3.  ΔG < 0

4.  ΔS > ΔH/T

4

ΔS > ΔH/T

Explanation :
No Explanation available for this question

Find out ΔG for the following reaction: 2ZnS +3O2→2ZnO+2SO2;ΔG= Data given: 2Zn +O2→2ZnO ;ΔG=-616J,2Zn +S2→2ZnS ;ΔG=-293J,,S2+2O2→2SO2;ΔG=-408J.

1.  -731 J

2.  -1317 J

3.  -510 J

4.  +731 J

4

-731 J

Explanation :
No Explanation available for this question

When potassium chloride is dissolved in water

1.  Entropy increases

2.  Entropy decreases

3.  Entropy increases and than decreases

4.  Free energy increases

4

Entropy increases

Explanation :
No Explanation available for this question

One mole of a non ideal gas undergoes a change of state (2.0atm, 3.0L,95K)→(4.0atm, 5.0L,245K)with a change in internal energy, ΔU=30.0L atm. The change in enthalpy (ΔH) of the process in L atm is

1.  40.0

2.  42.3

3.  44.0

4.  Not defined because pressure is not constant.

4

44.0

Explanation :
No Explanation available for this question

Which of the following pairs has heat of neutralisation equal to -57.1kJ

1.  HNO3. KOH

2.  HCl. NH4OH

3.  H2SO4, NH4OH

4.  CH3COOH,NaOH

4

HNO3. KOH

Explanation :
No Explanation available for this question

The variation of heat of reaction with temperature is given by an equation known as

1.  Van't Hoff equation

2.  Van der Waals equation

3.  Kirchhoffs equation

4.  Gibbs Helmholtz equation

4

Kirchhoffs equation

Explanation :
No Explanation available for this question

For which of the following reactions, ΔH is equal to ΔU

1.  N2(g)+3H2(g)→2NH3(g)

2.  PCl5(g)→PCl3(g)+Cl2(g)

3.  2H2S(g)+3O2(g)→2H2O(l)+2SO2(g)

4.  C(s)+O2(g)→CO2(g)

4

C(s)+O2(g)→CO2(g)

Explanation :
No Explanation available for this question

The temperature of the system decreases in an

1.  Isothermal compression

2.  Isothermal expansion

3.  Isothermal compression

4.  Isothermal expansion

4

Isothermal expansion

Explanation :
No Explanation available for this question

The heat change for a hypothetical reaction at constant pressure A2B(s)+2C(g)→2AC (g) +1/2B2(l)is +102.6kJ. The heat change for the above reaction at constant volume is

1.  -102.6 kJ

2.  102.6 kJ

3.  Less than 102.6 kJ

4.  Greater than 102.6 kJ

4