A buffer is prepared by dissolving \(\mathrm{HONH}_{2}\) and \(\mathrm{HONH}_{t} \mathrm{NO}_{3}\) in some water. Write equations to show how this buffer neutralizes added \(\mathrm{H}^{+}\) and \(\mathrm{OH}^{-}\)

A buffer solution is a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid. Buffer solutions resist changes in pH when small amounts of strong acids or bases are added. In this exercise, we have a buffer solution prepared by dissolving HONH2 and HONH2NO3.

First, we must determine the acidic and basic components of the buffer solution. We can do this by considering the dissociation of the given substances in water: HONH2 can donate a proton (H+) to form its conjugate base: HONH2 \( \rightleftharpoons \) HONH- + H+ HONH2NO3 is the salt of HONH2 and HNO3, formed by the reaction of HONH2 (weak base) and HNO3 (strong acid): HONH2 + HNO3 \( \rightarrow \) HONH2NO3 + H2O Since HNO3 is a strong acid, its dissociation in water can be considered complete: HNO3\( \rightarrow \) H+ + NO3- The dissociation of HONH2NO3 will therefore be: HONH2NO3\( \rightleftharpoons \) HONH2 + NO3- So, in this buffer: - HONH2 (a weak base) serves as the basic component. - The HONH2NO3 (the salt of HONH2) ionizes in water to produce HONH2 and NO3-, where NO3- is the conjugate base of the strong acid HNO3, serving as the acidic component.

Now, we will write the equations that show how the buffer's components neutralize added H+ and OH- ions. Neutralizing added H+: When H+ ions are added to the buffer, the basic component HONH2 reacts with the H+ ions to form its conjugate acid: HONH2 + H+ \( \rightarrow \) HONH3+ Neutralizing added OH-: When OH- ions are added to the buffer, the acidic component (NO3- ions from HONH2NO3) reacts with the OH− ions to form water and the conjugate base HONH2: HONH2 + OH- \( \rightarrow \) HONH- + H2O In summary, the buffer consisting of HONH2 and HONH2NO3 neutralizes added H+ ions through the following reaction: HONH2 + H+ \( \rightarrow \) HONH3+ And it neutralizes added OH- ions through this reaction: HONH2 + OH- \( \rightarrow \) HONH- + H2O