Hydrogen sulfide, H2S(g), is a colourless, toxic, flammable gas. Its main use is in the qualitative inorganic analysis of certain metal ions. Hydrogen sulfide gas ionizes in water as shown below:
H2S(aq) + H2O (l) → H3O+(aq) + HS–(aq)
At equilibrium, which of the following statements is correct?
a) Reactants are favoured.
b) Products are favoured.
c) One of the reactants and one of the products are favoured.
d) The concentration of reactants and products are equal.
e) The equilibrium will lie to the right.
The correct answer is d) The concentration of reactants and products are equal.
At equilibrium, the concentrations of reactants and products reach a balanced state where the rate of the forward reaction is equal to the rate of the reverse reaction. This means that the concentrations of reactants and products remain constant over time. In this case, the concentrations of H2S(aq) and H2O(l) will be equal to the concentrations of H3O+(aq) and HS–(aq) respectively, indicating that the concentration of reactants and products are equal.
are you sure?
I apologize for the confusion. I made an incorrect statement in my previous response. The correct answer is b) Products are favored.
In the given equilibrium reaction, the formation of H3O+(aq) and HS–(aq) from H2S(aq) and H2O(l) is favored. This means that at equilibrium, the concentration of the products (H3O+(aq) and HS–(aq)) will be greater than the concentration of the reactants (H2S(aq) and H2O(l)).
Thank you for pointing out the error, and I apologize for any confusion caused.
What is the correct answer?
I apologize for the confusion. The correct answer is c) One of the reactants and one of the products are favored.
At equilibrium, the concentration of reactants and products will not be equal. In this case, the H2S(aq) and H2O(l) will be one of the reactants that is favored and H3O+(aq) and HS–(aq) will be one of the products that is favored. The equilibrium constant expression for this reaction is K = [H3O+(aq)][HS–(aq)] / [H2S(aq)][H2O(l)].
To determine the correct statement at equilibrium, we need to consider the reaction and the context provided. The given reaction is the ionization of hydrogen sulfide gas (H2S) in water, which forms hydronium ions (H3O+) and sulfide ions (HS–). Now, let's analyze the options:
a) Reactants are favored: This means that the reaction prefers the species on the left side (H2S(aq) + H2O(l)). However, since hydrogen sulfide is ionizing in water, forming both H3O+ and HS–, it cannot solely favor the reactants.
b) Products are favored: This means that the reaction prefers the species on the right side (H3O+(aq) + HS–(aq)). Since the ionization reaction occurs in an aqueous solution, it is reasonable to assume that the products should be favored to some extent. However, we cannot conclude that the products are solely favored.
c) One of the reactants and one of the products are favored: It is possible that both the reactants and products are favored to some degree. As mentioned earlier, since the reaction occurs in an aqueous solution, the products are likely to be favored. However, we cannot disregard the possibility of the reactants also being favored to some extent.
d) The concentration of reactants and products are equal: This option states that at equilibrium, the concentrations of the reactants and products are equal. However, according to Le Chatelier's principle, in a system at equilibrium, the reaction will adjust to minimize the effect of any changes. Since water is a solvent and can break down some of the initial H2S, it is unlikely that the concentrations of the reactants and products would be exactly equal.
e) The equilibrium will lie to the right: This option suggests that the reaction predominantly proceeds in the forward direction (in this case, from left to right). Considering that the ionization reaction occurs in an aqueous solution, it is reasonable to conclude that the equilibrium will indeed lie towards the right, favoring the formation of H3O+ and HS– ions.
Based on the analysis, the correct statement in this case would be: e) The equilibrium will lie to the right.