Express the pH to two decimal places ANSWER Correct The buffer composed of 012

Express the ph to two decimal places answer correct

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Express the pH to two decimal places. ANSWER: Correct The buffer composed of 0.12 of propionic acid and 9.0 × 10 2 of its conjugate base, propionate, is made more basic through the addition of a strong base, . Therefore, the values of the weak acid and its conjugate weak base should be adjusted accordingly. The appropriate Henderson-Hasselbalch equation, using the amounts in moles, is Part C What is the of the buffer after the addition of 0.02 of ? Express the pH to two decimal places. ANSWER: Correct The buffer composed of 0.12 of propionic acid and 9.0 × 10 2 of its conjugate base, propionate, is made more acid through the addition of a strong acid, . Therefore, the values of the weak acid and its conjugate weak base should be adjusted accordingly. The appropriate Henderson- Hasselbalch equation, using the amounts in moles, is Problem 17.24 Custom A buffer is prepared by adding 11.0 of ammonium chloride to 230 of 1.00 solution. Part A pH = 4.76 pH mol mol pK a pH pH pH = p + log K a 9.0 × mol 10 2 0.12mol pH mol NaOH = 4.93 pH mol mol NaOH pH = 4.9 + log 9.0 × mol+0.02mol 10 2 0.12mol 0.02mol pH mol HI = 4.59 pH mol mol HI pH = 4.9 + log 9.0 × mol 0.02mol 10 2 0.12mol+0.02mol g (N Cl) H 4 mL MNH 3 pH
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4/4/15, 12:51 PM Hw17-Chapter17 Page 9 of 32 What is the of this buffer? ANSWER: Correct Part B Write the net ionic equation for the reaction that occurs when a few drops of nitric acid are added to the buffer. Express your answer as a chemical equation. Identify all of the phases in your answer. ANSWER: Correct Part C Write the net ionic equation for the reaction that occurs when a few drops of potassium hydroxide solution are added to the buffer. Express your answer as a chemical equation. Identify all of the phases in your answer. ANSWER: Correct ± Titrations Custom Learning Goal: To learn about titration types and how to calculate at different points of titration. In an acid-base titration, a titrant (solution of a base or acid) is added slowly to an analyte (solution of an acid or base). The titration is often monitored using a meter. A plot of as a function of the volume of titrant added is called a titration curve . Prior to the titration, the is determined by the concentration of the analyte. When the titrant is added, it begins to neutralize the analyte. The decrease in the analyte concentration changes the . At the equivalence point , equivalent quantities of acid and base have been mixed together such that the acid-base reaction is complete, and the is determined by the product. In the case of a strong acid-strong base titration, the salt formed is neutral, and . In a weak acid-strong base titration, a basic salt is produced, and . In a weak base-strong acid titration, the salt is acidic, and . After the equivalence point, the is determined by the concentration of excess titrant.
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