Question

8) Given the following equation, C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) ΔG°rxn = -2074 kJ

Calculate ΔG°rxn for the following reaction.

21 CO2(g) + 28 H2O(g) → 7 C3H8(g) + 35 O2 g)

A) +14518 kJ B) -2074 kJ C) -14518 kJ D) -296 kJ E) +2074 kJ

22) Given the following equation, C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) ΔG°rxn = -2074 kJ

Calculate ΔG°rxn for the following reaction.

7 C3H8(g) + 35 O2(g) → 21 CO2(g) + 28 H2O(g)

A) -14518 kJ B) +2074 kJ C) -2074 kJ D) -296 kJ E) +14518 kJ

29) Given the following equation, H2O(g) + CO(g) → H2(g) + CO2(g) ΔG°rxn = -28.6 kJ

Calculate ΔG°rxn for the following reaction.

5 H2(g) + 5 CO2(g) → 5 H2O(g) + 5 CO(g)

A) +143.0 kJ B) -28.6 kJ C) -143.0 kJ D) +5.72 kJ E) -5.72 kJ

Answer 1

8) Given the following equation, C3H8(g) + 5 O2(g) ? 3 CO2(g) + 4 H2O(g) ?G°rxn = -2074 kJ

Calculate ?G°rxn for the following reaction.

21 CO2(g) + 28 H2O(g) ? 7 C3H8(g) + 35 O2 g)

Solution :-

The orginal equation is reversed and multiplied by 7 therefore the sign of the delta G changes and it is multiplied by the 7

So the Delta G for the new equation = 2074 kJ *7 = +14518 kJ

So the correct answer is option A

22) Given the following equation, C3H8(g) + 5 O2(g) ? 3 CO2(g) + 4 H2O(g) ?G°rxn = -2074 kJ

Calculate ?G°rxn for the following reaction.

7 C3H8(g) + 35 O2(g) ? 21 CO2(g) + 28 H2O(g)

Solution :- Original equation is multiplied by 7 therefore the

Delta G for the new equation = -2074 kJ * 7 = -14518 kJ

So the correct answer is option A

29) Given the following equation, H2O(g) + CO(g) ? H2(g) + CO2(g) ?G°rxn = -28.6 kJ

Calculate ?G°rxn for the following reaction.

5 H2(g) + 5 CO2(g) ? 5 H2O(g) + 5 CO(g)

Solution :- Original equation is multiplied by 5 and reversed

Therefore the delta G for the new equation = 28.6 kJ *5 = +143.0 kJ

So the correct answer is option A