In the carbonic acid equilibrium system, what happened to the size of the size of the balloon upon addition of more acid (HCl) and also what happened to the balloon upon addition of NaOH, was this expected? why or why not. ( show answers using equilibrium equation.
To understand what happens to the size of the balloon in the carbonic acid equilibrium system upon addition of more acid (HCl) or NaOH, we need to examine the equilibrium equation for the dissociation of carbonic acid (H2CO3).
The equilibrium equation for the dissociation of carbonic acid is:
H2CO3 ⇌ H+ + HCO3-
When more acid (HCl) is added to the system, it increases the concentration of H+ ions (hydrogen ions) on the right side of the equation. According to Le Chatelier's principle, if a stress is applied to a system in equilibrium, the system will shift in a way that minimizes the stress.
In this case, the increased concentration of H+ ions due to the addition of HCl would cause the equilibrium to shift to the left to minimize the stress. As a result, some of the H+ ions would combine with the bicarbonate ions (HCO3-) to reform carbonic acid (H2CO3). The reduction in H+ ions would decrease the concentration of hydrogen ions and, consequently, decrease the acidity of the solution.
Since carbonic acid is a weak acid, a decrease in acidity leads to a decrease in the concentration of H+ ions. This decrease in acidity would cause the balloon in the system to shrink in size, as the lower concentration of H+ ions reduces the pressure and the volume of the gas in the balloon.
On the other hand, if NaOH (a strong base) is added to the system, it would introduce OH- ions (hydroxide ions) into the solution. According to the equilibrium equation, the increase in OH- ions would react with H+ ions to form water (H2O). This reaction would cause the equilibrium to shift to the right to consume the OH- ions and minimize the stress.
As a result, the decrease in H+ ions due to the reaction with OH- ions would increase the concentration of carbonic acid (H2CO3), leading to an increase in acidity. This increase in acidity would cause the balloon in the system to expand in size, as the higher concentration of H+ ions increases the pressure and the volume of the gas in the balloon.
Therefore, upon addition of more acid (HCl), the balloon would shrink in size, whereas upon the addition of NaOH, the balloon would expand in size. These observations are expected based on the equilibrium equation and the principles of Le Chatelier's principle.