The difference between ΔH and ΔU ( ΔH- ΔU), when the combustion of one mole heptane(I) is carried out a temperature T, is equal to:

• -3RT

• -4RT

• 3RT

• 4R

Which of the following statement is correct for the spontaneous absorption of a gas?

• ΔS is negative and therefore, ΔH should be highly positive
  
• ΔS is negative and therefore, ΔH should be highly negative
• ΔS is positive and therefore, ΔH should be negative
• ΔS is positive and therefore, ΔH should be negative

For the reaction X₂O₄ (l) -->  2XO₂ (g) ΔU = 2.1 kcal, ΔS = 20 cal K^-1 at 300 K hence ΔG is

• 2.7 kcal

• -2.7kcal

• 9.3 kcal 

• 9.3 kcal 

Which of the following statements is correct for a reversible process in a state of equilibrium?

• ΔG = -2.303RT log K

• ΔG = 2.303RT log K

• ΔG⁰ = -2.303RT log K

• ΔG⁰ = -2.303RT log K

The correct thermodynamic conditions for  the spontaneous reaction at all temperatures is

• ΔH> 0 and Δ S< 0
• ΔH< 0 and ΔS > 0
• ΔH ΔS >0
• ΔH ΔS >0