5. Buffer and pH problems. Show your work below the problems (and on the other side of this needed), but please write your final answer in the blank next to the question. page, if A. What is the pH if 40.00 mL 0.0045M HCI is added to 140.0 mL dH20? B. What is the pH if 15.0 mL of 0.064M NaOH is added to 70.0 mL dH20? C. What is the pH if 30.0 mL of 0.20M NaH2PO4 was mixed with 35.0 mL of 0.30M NazHPO4? The pKa values of phosphate are 2.14, 7.20 and 12.40.

Question Completion Status: For Solution A, approximately how many mL of HCI were needed to exceed the buffering capacity of this solution? Enter the number only. Don't enter units as part of your answer and don't use commas or scientific notation. Titration curve of Solution A 14 13 12 11- 10 9 8 pH 7 6 5 4 3 2 1 5 4 3 2 1 HCI added (mL) 0 1 2 3 4 5 NaOH added (mL) 14 13 12- 11 10 9 8 pH 7 6.8 2 65 4 3 2 1 Titration curve of Solution B Click Save and Submit to save and submit. Click Save All Answers to save all answers. 54 32 1 HCI added (mL) 0123 NaOH added (mL)

The reason a buffer is able to maintain its pH against the addition of a strong acid or base is...b) Both buffer compounds will neutralize the added strong acid or base.a) Both of the buffer compounds will cause a Le Chatelier’s shift.c) One of the 2 buffer compounds will cause a right Le Chatelier’s shift.d) One of the 2 buffer compounds will cause a left Le Chatelier’s shift.

How does the solubility of Acetic Acid change when the pH is adjusted? Why did the solubility change or not change? Draw out the reaction of the Acetic Acid with acid and base.