In Order to determine equivalence points required looking at graphs and values

# In order to determine equivalence points required

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In Order to determine equivalence points required looking at graphs and values, all other calculations involved formulas below. pK a =-log 10 (K) pK a =pH+log 10 ([AH]/[A-]) pK a =pH+log 10 (conjugated acid/conjugated base) pK a1 the point plotted was 1.85 10^-1.85=1.4*10^-2= K a1 C.) Claim The exact initial concentration for H 3 PO 4 is .306 this is determined by the change of the first equivalent point versus the second. In order to determine the pK a1 and pK a2 for H 3 PO 4 , you need to analyze the graph and find the equivalent point. Once the values are found for pK a1 the point plotted was 1.85. Using the same method to determine pK a2 the value is 6.97. To find K a1 and K a2 for H 3 PO 4 we take ten raised to the negative power of the value of pK a1 and pK a2 . By doing this we get K a1 with a value of 1.4*10^-2 and K a2 1.07*10^-7. The average H 3 PO 4 concentration in my soft drink is .00745, the concentration can be determined by the number of moles over the volume. (Question 2& 3 shown in calculations above) D.) Evidence For question one we were able to determine this from the equivalence points on the graphs. We are able to determine this information for Evidence for research question number two is seen from the graphs. By understanding where the #### You've reached the end of your free preview.

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• Fall '11
• U
• Chemistry, pH, Pk, Equivalence point, Phosphoric acid, Equiv. pH
• • •  