Concept explainers
Interpretation:
The hydrogen bonding possible between G-C base pair when both bases are in their enol form is to be drawn. Comparing this with the hydrogen bonding in the base pair shown in Figure 14-31 and Figure 14-33, which scenario maximizes hydrogen bonding is to be determined.
Concept introduction:
A hydrogen bond is a form of dipole-dipole interaction. It occurs between a hydrogen atom bonded to a highly electronegative atom like N, O, or F and an atom of one of these from another molecule. It is also possible for the two groups to be from the same molecule. H-bond is formed when the electronegative atom from one molecule/group donates its lone pair to the partially positively charged hydrogen-bonded to the electronegative atom.
Compounds containing an enol group – an OH bonded to a carbon double-bonded to another carbon – generally rearrange to the more stable keto form in a process known as tautomerization.
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Organic Chemistry: Principles and Mechanisms (Second Edition)
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- 14-48 Explain why methanethiol, CH3SH, has a lower boiling point (6°C) than methanol, CH3OH (65°C), even though methanethiol has a higher molecular weightarrow_forward17-26 Account for the fact that acetone has a higher boiling point (56°C) than ethyl methyl ether (11°C) even though their molecular weights are almost the same.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
- 14-23 Arrange these compounds in order of increasing boiling point. Values in °C are 0, 35, and 97. CH3CH2CH2OH CH3CH2OCH2CH3 ch3ch2ch2ch3arrow_forward14-61 Knowing what you do about electronegativity, the polarity of covalent bonds, and hydrogen bonding, would you expect an N—H—N hydrogen bond to be stronger than, the same strength as, or weaker than an O—H—O hydrogen bond?arrow_forwardplease explain what 4 things will we be testing on the carboxylic acid required in lab procedure required? 1 pH 2 solubility in cold water 3 oxidation 4 solubility in hot water 5 neutralization 6 saturationarrow_forward
- 14-71 The mechanism of the acid-catalyzed dehydration of an alcohol to an alkene is the reverse of the acid- catalyzed hydration of an alkene. The dehydration mechanism occurs by the following three steps. Step 1: Add a proton. Step 2: Break a bond to form stable molecules or ions. Step 3: Take away a proton. These three steps are illustrated here by the dehydration of 2-butanol to give 2-butene. Use curved arrows to show the flow of electrons in each step; that is, show how each bond-making or bond-breaking step occurs. H I + Step 3: CH3—CH—CH—CH3 CH3—CH=CH—CH3 + H + 2-butenearrow_forward5) Ethyne (CH≡CH) has a pKa of 25 and water has pKa of 15.7 and ammonia (NH3) has a pKa of 36. Write equilibrium reactions showing arrows that indicate whether the reactants or products are the favored for reaction of Ethyne with a. HO- , and b. with NH2 - and indicate which one is better for removing proton from Ethyne. Then calculate the equilibrium constants, Ke, for each equilibrium reaction. Are calculated Ke values match the expected results from prediction you made .arrow_forward14-20 Show hydrogen bonding between methanol and water in the following ways. Between the oxygen of methanol and a hydrogen of water Between the hydrogen of methanol’s OH group and the oxygen of waterarrow_forward
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