Concept explainers
Interpretation:
The more stable structure of two possible structures for the conjugate acid of guanidine is to be identified, and resonance structures showing electron delocalization are to be drawn.
Concept introduction:
According to the resonance concept, Lewis formulas that have different distribution of electrons in their structure can be written for a single molecule. Lewis formulas that confer to a resonance hybrid can be made easier to understand by using curved arrows to represent the delocalized electrons.
Each structure contributing to resonance must have an equal total number of valence electrons and the same value of net charge. Among the various Lewis formulas written for a molecule, the formal charges on individual atoms may vary. Each structure contributing to resonance must have the same number of unshared electrons.
When two or more structures satisfy the octet rule, the major contributor structure is the one with the smallest separation of oppositely charged atoms. The contributor structure with the least number of formal charges is more stable.
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Organic Chemistry - Standalone book
- An electrostatic potential map of calicene is shown below. a) Both the electrostatic potential map and its significant dipole moment indicate that calicene is an unusually polar hydrocarbon. Which of the dipolar resonance forms, structure A or structure B, better corresponds to the electron distribution in the molecule? Select the single best answer. b) Which one of the following structures should be stabilized by resonance to a greater extent? Select the single best answer.arrow_forwardWouldn't the oxygen be protonated since it becomes more electronegative through resonance and more willing to accept a proton?arrow_forwardThe hydrophobic effect is one of the most important noncovalent forces directing the self-assembly of biomolecules in aqueous solution. The hydrophobic effect arises from tendencies of biomolecules (1) to arrange polar groups so that they interact with the aqueous environment by hydrogen bonding and (2) to arrange nonpolar groups so that they are shielded from the aqueous environment. Show how the hydrophobic effect is involved in directing the following. Q.) The formation of lipid bilayers by phospholipidsarrow_forward
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- Define the consequence of resonance stabilization ?arrow_forwardIn this chapter, we did not discuss the interaction that is primarily responsible for the attraction that exists between an anion like CH30¯ and a nonpolar molecule like Br2. (a) What name would be ascribed to the strongest interaction that exists between those two species? (b) For which pair of species would you expect that type of attractive interaction to be stronger: between CH30¯ and Br2 or between CH30¯ and I2? Why?arrow_forwardWhich of the following are examples of isobars? S-40 & CI-40 S-32 & P-31 Na-37 & K-39 C-12 & C-14arrow_forward
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning