In all of our experiments up to this point, we have discovered the pH values of our household cleaners, alkaline water, and solutions. However, how can we use Sarah's pOH calculations to find the concentration of Windex before and after dilution. Below is the following chemical equation we used in the experiment:
NH3 + H20 --> NH4 + OH
If the pH level of NH3 at the start of the experiment was 10, then its pOH was 4. Using the formula [OH] = 10 ^ (-pOH), the molarity of the OH ion would be 1.0 x 10 ^ -4 M. However, once the reaction completes, the remaining portion of the Windex, or NH4, would be the conjugate acid. Using the pH value of 9, the molarity of the H30 ion (hydronium) would be 1.0 x 10 ^ -9 M. When diluted with water, the concentration of the original substance drastically decreases, proving our data accurate.
-Gretchen Koomjohn