User:Patrick Hampson/Notebook/chem471/2017/02/01

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Investigating the UV-Vis activity of Gold-Hydroxide complexes Au(OH)x pH scheming As we increase the pH of our solutions, we are increasing the [OH]. The higher [OH] means that more "Au(OH)x"s are likely to form, as (OH) substitute in for Cl-. A great extent of this lab time was used to do pH calculations and planning. Our Deionized H2O has a pH of 5.7, which corresponds to a pOH of 8.3 or [OH]=10^-8.3 moles/Liter. We will neutralize the water to pH 7 using either NaOH, or a buffer solution of it comes to that. We will use equal parts 5mM NaOH and 5mM HAuCl4, as a strong base should counteract a strong acid, in theory. This should prevent any major shifts in the pH of our solution. Any acidic solutions, we will rely on our 5mM HAuCl4 to bring the pH down to our desired values. Any basic solutions, we will rely on our 5mM and 1 M NaOH to raise the solution to our desired values.