When h2 and co2 react, acetic acid can be formed spontaneously while the production of formaldehyde requires an input of energy.
which of the following conclusions may be drawn from this observation?
a) the mineral catalyst involved in acetic acid production provides energy to make the reaction spontaneous.
b) more heat is released when formaldehyde is produced compared to the production of acetic acid.
c) entropy decreases when acetic acid is produced and increases when formaldehyde is produced.
d) compared to the reactants from which it is formed, formaldehyde has more potential energy than does acetic acid.

D) Compared to the reactants from which it is formed, formaldehyde has more potential energy than does acetic acid.

Explanation:

A reaction ocurrs spontaneously  meanly in two cases, when reaction release energy (exothermic reaction) or when the entropy of the system increases.

Option A is false because if reaction needs a catalyst, this reaction in not spontaneous and catalyst don´t provide energy to reaction, only gives a hand to it ocurrs.

In opton B when formaldehyde is produced reaction release heat, so this is the spontaneous reaction, contrary to what was observed.

In option C entropy increases when  formaldehyde is produced, also  in this case is the spontaneous reaction, contrary to what was observed.

But in option D potential energy of acetic acid is smaller than reactants, it means that energy is release as a heat and reaction ocurrs spontaneously.

By the other hand potential energy of  formaldehyde is higher than reactants and needs energy to ocurrs.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.