Calculate the pH of each of the following solutions. a. 0.12\(M \mathrm{KNO}_{2}\) b. 0.45 \(\mathrm{MNaOCl}\) c. 0.40 \(\mathrm{M} \mathrm{N} \mathrm{a} \mathrm{OCl}\)

For each substance (KNO2, NaOCl, and NaOCl), we need to first determine their respective ion concentrations. a. KNO2 is a salt that dissolves in water to form K+ ions and NO2- ions. Since the solution has a concentration of 0.12 M, it indicates that both K+ and NO2- ions have a concentration of 0.12 M. b. NaOCl is a salt that dissolves in water to form Na+ ions and OCl- ions. The solution has a concentration of 0.45 M, which means both Na+ and OCl- ions have a concentration of 0.45 M. c. NaOCl is also a salt that dissolves in water to form Na+ ions and OCl- ions, as in the former case. The solution has a concentration of 0.40 M, meaning both the Na+ and OCl- ions have a concentration of 0.40 M.

Now let's determine the concentration of H+ ions in each solution. We will focus on the anions (NO2- and OCl-) to calculate the H+ ion concentration. a. NO2- ion reacts with water to form HNO2 and OH- ions. \(NO_{2}^{-} + H_{2}O \rightleftharpoons HNO_{2} + OH^-\) We can use the Kb value of NO2- to determine the concentration of H+ ions in the solution. For KNO2, we know that: \(Kb = [OH^{-}] / [NO_{2}^{-}]\) Next, we will use the relationships between Ka and Kb, and Kw to find the concentration of H+ ions: \(Ka * Kb = Kw\) \(Ka = Kw / Kb\) We can find the concentration of H+ ions using the Ka value: \(Ka = [H^{+}]^2 / [HNO_{2}]\) b. OCl- ion reacts with water to form HOCl and OH- ions. \(OCl^{-} + H_{2}O \rightleftharpoons HOCl + OH^-\) For NaOCl, we will follow the same procedure as for KNO2, using the Kb value of OCl- ion and Kw to find the concentration of H+ ions. c. In the case of the 0.40 M NaOCl solution, we follow the same procedure as for the 0.45 M NaOCl solution.

Once we have the concentration of H+ ions for each solution, we can use the pH formula to calculate the pH: pH = -log[H+] a. Calculate the pH for the 0.12 M KNO2 solution using the H+ ion concentration determined in step 2. b. Calculate the pH for the 0.45 M NaOCl solution using the H+ ion concentration determined in step 2. c. Calculate the pH for the 0.40 M NaOCl solution using the H+ ion concentration determined in step 2.