Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Chapter 20.SE, Problem 64AP
The following pKa values have been measured. Explain why a hydroxyl group in the para position decreases the acidity while a hydroxyl group in the meta position increases the acidity.
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Explain why p-nitrophenol (the left molecule) is more acidic than p-methylphenol (the right
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a
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Phenol has a pka = 10.0. 4-Hydroxybenzaldehyde has a pka = 7.3. Draw resonance forms of the
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OH
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1. Rank the following species in order of increasing acidity. Explain your reasons for ordering them as you do. HF NH3 H2SO4 CH3OH CH3COOH H3O+ H2O2.
Consider the following compounds that vary from nearly nonacidic to strongly acidic. Draw the conjugate bases of these compounds, and explain why the acidity increases so dramatically with substitution by nitro groups.
CH4 CH3NO2 CH2(NO2)2 CH(NO2)3
Chapter 20 Solutions
Organic Chemistry
Ch. 20.1 - Give IUPAC names for the following compounds:Ch. 20.1 - Draw structures corresponding to the following...Ch. 20.2 - Prob. 3PCh. 20.2 - The Ka for dichloroacetic acid is 3.32 Ă— 10-2....Ch. 20.3 - Calculate the percentages of dissociated and...Ch. 20.4 - Which would you expect to be a stronger acid, the...Ch. 20.4 - Dicarboxylic acids have two dissociation...Ch. 20.4 - The pKa of p-cyclopropylbenzoic acid is 4.45. Is...Ch. 20.4 - Prob. 9PCh. 20.5 - Prob. 10P
Ch. 20.6 - Prob. 11PCh. 20.6 - How might you carry out the following...Ch. 20.7 - Prob. 13PCh. 20.7 - Prob. 14PCh. 20.8 - Cyclopentanecarboxylic acid and...Ch. 20.8 - Prob. 16PCh. 20.SE - Prob. 17VCCh. 20.SE - Prob. 18VCCh. 20.SE - The following carboxylic acid can’t be prepared...Ch. 20.SE - Electrostatic potential maps of anisole and...Ch. 20.SE - Predict the product(s) and provide the mechanism...Ch. 20.SE - Predict the product(s) and provide the mechanism...Ch. 20.SE - Prob. 23MPCh. 20.SE - Predict the product(s) and provide the complete...Ch. 20.SE - Acid-catalyzed hydrolysis of a nitrile to give a...Ch. 20.SE - Prob. 26MPCh. 20.SE - Naturally occurring compounds called cyanogenic...Ch. 20.SE - 2-Bromo-6, 6-dimethylcyclohexanone gives 2,...Ch. 20.SE - Naturally occurring compounds called terpenoids,...Ch. 20.SE - In the Ritter reaction, an alkene reacts with a...Ch. 20.SE - Give IUPAC names for the following compounds:Ch. 20.SE - Prob. 32APCh. 20.SE - Prob. 33APCh. 20.SE - Prob. 34APCh. 20.SE - Prob. 35APCh. 20.SE - Prob. 36APCh. 20.SE - Prob. 37APCh. 20.SE - Prob. 38APCh. 20.SE - Calculate the Ka's for the following acids: (a)...Ch. 20.SE - Thioglycolic acid, HSCH2CO2H, a substance used in...Ch. 20.SE - Prob. 41APCh. 20.SE - Prob. 42APCh. 20.SE - How could you convert butanoic acid into the...Ch. 20.SE - How could you convert each of the following...Ch. 20.SE - How could you convert butanenitrile into the...Ch. 20.SE - How would you prepare the following compounds from...Ch. 20.SE - Prob. 47APCh. 20.SE - Using 13CO2 as your only source of labeled carbon,...Ch. 20.SE - Prob. 49APCh. 20.SE - Which method-Grignard carboxylation or nitrile...Ch. 20.SE - Prob. 51APCh. 20.SE - Prob. 52APCh. 20.SE - Propose a structure for a compound C6H12O2 that...Ch. 20.SE - Prob. 54APCh. 20.SE - How would you use NMR (either 13C or 1H) to...Ch. 20.SE - Prob. 56APCh. 20.SE - A chemist in need of 2,2-dimethylpentanoic acid...Ch. 20.SE - Prob. 58APCh. 20.SE - Prob. 59APCh. 20.SE - Prob. 60APCh. 20.SE - Prob. 61APCh. 20.SE - Prob. 62APCh. 20.SE - Prob. 63APCh. 20.SE - The following pKa values have been measured....Ch. 20.SE - Identify the missing reagents a-f in the following...Ch. 20.SE - Propose a structure for a compound, C4H7N, that...Ch. 20.SE - Prob. 67APCh. 20.SE - The 1H and 13C NMR spectra below belong to a...Ch. 20.SE - Propose structures for carboxylic acids that show...Ch. 20.SE - Carboxylic acids having a second carbonyl group...
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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
- pKa of CF3CH2OH is higher than the pKa of a CCl3CO2H. Provide the reason Group of answer choices a) The conjugate base of CCl3CO2H is more stabilized than the conjugate base of CF3CH2OH b) The conjugate base of CCl3COH is stabilized by type of atom c) CF3CH2OH is stronger acid d) The conjugate base of CCl3CO2H is less stabilized than the conjugate base of CF3CH2OH e) Fluorine is more electronegative than Clarrow_forwardMy selection was incorrect - what else can the answer be?arrow_forwardAlthough p-hydroxybenzoic acid is less acidic than benzoic acid, o-hydroxybenzoic acid is slightly more acidic than benzoic acid. Explain this result. OH но -COOH -соон p-hydroxybenzoic acid o-hydroxybenzoic acidarrow_forward
- 7. Draw the conjugate base for each. CH;CH2OH → CH:CH;CH3 → CH:CH2NH2 – CH:CH2SH –arrow_forwardConsider the following compounds that vary from nearly nonacidic to strongly acidic. Draw the conjugate bases of these compounds, and explain why the acidity increases so dramatically with substitution by nitro groups.refer to the photoarrow_forwardBr O-H Rank the following carboxylic acids from lowest to highest pka. Remember, a low pKa is more acidic than a high pKa. A 1 O-H B 4 Compound 1 Br Compound 2 ་་་་་ Compound 3 0 D 4 1 Compound 4 E 2arrow_forward
- Although p-hydroxybenzoic acid is less acidic than benzoic acid, ohydroxybenzoic acid is slightly more acidic than benzoic acid. Explainthis result.arrow_forwardI know that the 3rd one (second on the right side) has the highest pka because it's an alcohol and an alcohol is less acidic than a phenol. but I don't understand which compound has the lowest pka (strongest acid)?arrow_forwardНО. meta-Hydroxyacetophenone HO para-Hydroxyacetophenone The conjugate base of the para isomer has a negative charge that is delocalized over atom(s), and the conjugate base of the meta isomer has a negative charge that is delocalized over oxygen atom(s). Therefore, the conjugate base of the meta isomer is carbon atom(s) and isomer, making meta-hydroxyacetophenone oxygen carbon atom(s) and stable than then conjugate base of the para ✓acidic than para-hydroxyacetophenone.arrow_forward
- Trifluoroethanol (CF3CH2OH, pKa = 12.5) is more acidic than ethanol (CH3CH2OH, pKa = 16). Provide a three-dimensional structure for each conjugate base and draw the orbitals for all lone pairs. Provide a succinct explanation for the greater acidity of trifluoroethanol.arrow_forwarda) Draw all resonance forms of 3-hydroxybenzaldehyde and of the corresponding conjugate base. W hich conclusions can you draw for its acidity (pKa) in comparison to phenol?| b) Draw all resonance forms of 3-hydroxybenzaldehyde and of the corresponding conjugate base. Which conclusions can you draw for its acidity (pKa) in comparison to phenol and 3-hydroxybenzaldehyde? c) Discuss the relative acidities of 2-hydroxybenzaldehyd und 4-hydroxybenzaldehyd.arrow_forwardComplete each acid-base reaction and predict whether the position of equilibrium lies toward the left or toward the right. (a) CH3CCH+CH3CH2ONa+CH3CH3OH (b) CH3CCCH2CH2OH+Na+NH2NH3(l)arrow_forward
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