# A mixture of 2 moles of carbon monoxide and one mole of oxygen in a closed vessel is ignited to get carbon dioxide. If ΔH is the enthalpy change and ΔU is the change in internal energy, then

1.  ΔH>ΔU

2.  ΔH

3.  ΔH=ΔU

4.  Not definite

4

ΔH<ΔU

Explanation :
No Explanation available for this question

# For a reaction to be spontaneous at all temperatures

1.  ΔG and ΔH should be negative

2.  ΔH=ΔG=0

3.  ΔG and ΔH should be positive

4.  ΔH

4

ΔG and ΔH should be negative

Explanation :
No Explanation available for this question

# In an endothermic reaction

1.  ΔH is negative

2.  Heat is given to the surroundings

3.  Enthalpy of the reactants is less than that of the products

4.  ΔE is negative

4

Enthalpy of the reactants is less than that of the products

Explanation :
No Explanation available for this question

# H2+1/2O2→H2O;ΔH=-68.39 kcal, K+H2O→KOH+12H2;ΔH=-48 kcal, KOH+water →KOH (aq) ,ΔH=-14 kcal The heat of formation of KOH in kals is

1.  -34.39 kcal

2.  102.39 kcal

3.  34.39 kcal

4.  130.39 kcal

4

102.39 kcal

Explanation :
No Explanation available for this question

# The standard enthalpy of formation, Δf H0 at 298Kfor methane, CH4(g)is -74.8kJ mol-1. The additional information required to determine the average energy for C-H bond formation would be

1.  Latent heat of vaporization of methane

2.  The first four ionization energies of carbon and electron gain enthalpy of hydrogen.

3.  The dissociation energy of hydrogen molecules, H2

4.  The dissociation energy of H2and enthalpy of sublimation of carbon

4

The dissociation energy of H2and enthalpy of sublimation of carbon

Explanation :
No Explanation available for this question

# The enthalpy change in freezing 1g of water (ΔH fusion =6.0kJ mol-1) will be

1.  -6000.0 J

2.  -333 J

3.  333.33 J

4.  60.0 J

4

-6000.0 J

Explanation :
No Explanation available for this question

# (ΔH-ΔU) for the formation of carbon monoxide (CO) from its elements of 298Kis (R=8.314JK-1mol-1)

1.  1238.78Jmol-1

2.  -2477.57Jmol-1

3.  2477.57Jmol-1

4.  -1238.78Jmol-1

4

1238.78Jmol-1

Explanation :
No Explanation available for this question

# When a solid is converted directly into gaseous state , the process is called sublimation. The entropy change during the process is

1.  Zero

2.  Negative

3.  Positive

4.  May be negative or zero

4

Positive

Explanation :
No Explanation available for this question

# The bond energies of C - C, C = C, H- H and C - H linkages are 350, 600, 400 and 410 kJ per mol respectively. The heat of hydrogenation of ethylene is

1.  -170kJ mol-1

2.  -260kJ mol-1

3.  -400kJ mol-1

4.  -450kJ mol-1

4

-170kJ mol-1

Explanation :
No Explanation available for this question

1.  736 K

2.  1050K

3.  1150 K

4.  11500C

4