Organic Chemistry
7th Edition
ISBN: 9780321803221
Author: Paula Y. Bruice
Publisher: Prentice Hall
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Textbook Question
Chapter 2, Problem 69P
a. If an add with a pKa of 5.3 is in an aqueous solutions of solution of pH 5.7, what percentage of the acid is present in its acidic form?
b. At what pH does 80% of the acid exist in its acidic form?
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11.The pKa of a weak acid was determined by measuring the pH of a solution
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Chapter 2 Solutions
Organic Chemistry
Ch. 2.1 - Which of the following are not acids? CH3COOH CO2...Ch. 2.1 - Draw the products of the addbase renc1 ion when a....Ch. 2.1 - a. What is the conjugate acid of each or the...Ch. 2.2 - a. Which is a stronger acid: one with a pKa of 5.2...Ch. 2.2 - An acid has a Ka of 4.53 106 in water. What is...Ch. 2.2 - Prob. 6PCh. 2.2 - Antacids are compounds that neutralize stomach...Ch. 2.2 - Are the following body fluids acidic or basic? a....Ch. 2.3 - Draw the conjugate acid of each of the following:...Ch. 2.3 - a. Write an equation showing CH3OH reacting as an...
Ch. 2.3 - Estimate the pKa values of the following...Ch. 2.3 - a. Which is a stronger base: CH3COO or HCOO? (The...Ch. 2.3 - Using the pKa values in Section 2.3, rank the...Ch. 2.4 - Prob. 14PCh. 2.5 - a. For each of the acid-base reactions in Section...Ch. 2.5 - Ethyne has a pKa value of 25, water has a pKa...Ch. 2.5 - Which of the following bases can remove a proton...Ch. 2.5 - Calculate the equilibrium constant for the...Ch. 2.6 - Rank the ions (CH3, NH2, HO, and F) from most...Ch. 2.6 - Rank the carbanions shown in the margin from most...Ch. 2.6 - Which is the stronger acid?Ch. 2.6 - Prob. 22PCh. 2.6 - Rank the halide ions (F, Cl, Br, and l) from...Ch. 2.6 - a. Which is more electronegative, oxygen or...Ch. 2.6 - Which is a stronger acid? a. HCl or HBr b....Ch. 2.6 - a. Which of the halide ions (F, Cl, Br, and l) is...Ch. 2.6 - Prob. 27PCh. 2.7 - What is a stronger acid? a. CH3OCH2CH2OH or...Ch. 2.7 - Prob. 29PCh. 2.7 - What is a stronger base?Ch. 2.8 - Fosamax (shown on the previous page) has six...Ch. 2.8 - Which is a stronger acid? Why?Ch. 2.8 - Prob. 34PCh. 2.9 - Using the table of pKa values given in Appendix I,...Ch. 2.10 - Prob. 36PCh. 2.10 - As long as the pH is not less than _______, at...Ch. 2.10 - A naturally occurring amino acid such as alanine...Ch. 2.10 - For each of the following compounds, indicate the...Ch. 2.11 - Write the equation that shows how a buffer made by...Ch. 2.12 - Draw the products of the following react ions. Use...Ch. 2.12 - What product are formed when each of the following...Ch. 2 - a. Rank the following alcohols from strongest to...Ch. 2 - Which is a stronger base? a. HS or HO b. CH3O or...Ch. 2 - According to the explanations by Lewis, if a...Ch. 2 - a. Rank the following carboxylic acids from...Ch. 2 - Prob. 51PCh. 2 - For the following compound. a. draw its conjugate...Ch. 2 - Rank the following compounds from strongest to...Ch. 2 - Prob. 54PCh. 2 - Prob. 55PCh. 2 - a. Rank the following alcohols from strongest to...Ch. 2 - For each compound, indicate the atom that is most...Ch. 2 - a. Given the Ka values, estimate the pKa value of...Ch. 2 - A single bond between two carbons with different...Ch. 2 - Tenormin, a member of the group of drugs known as...Ch. 2 - From which of the following compounds can HO...Ch. 2 - a. For each of the following pairs of reactions,...Ch. 2 - Prob. 63PCh. 2 - Which is a stronger acid? a. b. c. d.Ch. 2 - Prob. 65PCh. 2 - Given that pH+ pOH = 14 and that the concentration...Ch. 2 - How could you separate a mixture of the following...Ch. 2 - Prob. 68PCh. 2 - a. If an add with a pKa of 5.3 is in an aqueous...Ch. 2 - Calculate the pH values of the following...Ch. 2 - Prob. 1PCh. 2 - Prob. 2PCh. 2 - Prob. 3PCh. 2 - Which of the reactions in Problem 3 favor...Ch. 2 - Prob. 5PCh. 2 - Prob. 6PCh. 2 - Prob. 7PCh. 2 - Which is the stronger acid? a. ClCH2CH2OH or...Ch. 2 - Prob. 9PCh. 2 - Prob. 10PCh. 2 - Which is a more stable base? Remembering that the...Ch. 2 - Which is the Stronger acid?Ch. 2 - Prob. 13PCh. 2 - a. Draw the structure of (CH3COOH (pKa = 4.7) at...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- 3. You want to make a pH=10.5 buffer using methylamine (CH;NH2) and its conjugate acid methylammonium (pKa 10.632). a. Write the balanced chemical equation showing how this buffer would neutralize strong acid. b. Write the balanced chemical equation showing how this buffer would neutralize strong base. c. Use the concepts from those two reactions and at least one more balanced chemical equation to explain why buffers work. d. Should buffers be prepared at high or low concentration? Why?arrow_forwardYou are asked to make a buffer of pH 3.4 and given the above acids. Of these acids, which would create a buffer with the best capacity against acids? Which would have the best buffering capacity against bases? Which could not be used at all for this project? Best against acids Best against bases Acid #1 has a pka of 3.15 Acid #2 has a pKa of 3.65 Acid #3 has a pKa of 4.23 Acid #4 has a pka of 4.79 Cannot be used Acid #2 Acid #1 Acid #4arrow_forwardIn my slide, there is a table summarizing the pKa values for different acids. (1) when ranking the acidity level (how strong the acids are), a low pKa means high acidity. Why is that? (2) Calculate the phosphoric acid solution pH when the ratio of [H2PO4-]/[H3PO4] is 0.8.arrow_forward
- Some weak acids and their pKa values are given below. Which one of these acids will have the STRONGEST conjugate base? Select one: a. Phenol; pKa = 10.00 b. Methanoic acid; pKa = 3.75 c. Bromoethanoic acid; pKa = 2.9 d. Methanol; pKa = 15.54arrow_forwardAjja what is the ph of a 0.10m solution of an acid with a pKa of 8.4?arrow_forward2arrow_forward
- If the concentration of an acid in solution is 2.2 times larger than the concentration of its conjugate base, and the pH of the solution is 3.5, what is the pKa of the acid? Include the answer to 3 significant figuresarrow_forwardThe pKa value is ammonia is 9.3. You are allergic to the odor of ammonia. You smelled an ammonia solution with the pH 9.3 yesterday and it was OK. Now you tried to smell the same solution but with the pH of 8.3. What will happen to your allergy symptom? How much better or worse it will be compared to yesterday? (e.g., ~5 times better or worse).arrow_forwardWhich statements about acid-base equilibria is/are Wrong? I. The pKa = log Ka. II. A strong acid has a negative pKa value. II. A stronger acid has a pKa with a larger value than a weaker acid. IV. The stronger the base, the smaller the pKa of its conjugate acid. Select one: O I, II, IV O II O , IV O II, IVarrow_forward
- Which solution is closest to the pKa? Calculate the pH of the solutions and the change in pH after adding 5.00 mL of 0.10-mol L-1 NaOH. Calculate the pH of the solutions and the change in pH after adding 5.00 mL of 0.10-mol L-1 HCl. Which solution is most resistant to pH change? Which solution is least resistant to pH change?arrow_forward1. What is the pH of a 0.2 M acetic acid solution where the Ka for acetic acid is 1.33 x 10-5 M. 2. What is the pH of a 0.1 M formic acid solution where the pka for formic acid is 3.77.arrow_forwardWhat is the pH of a solution containing 0.50 moles of benzoic acid and 0.75 moles of sodium benzoate if the pka is 4.19?arrow_forward
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