6. How many peaks would be observed for each of the circled protons in the compounds below? 8 pts CH3 CH3 ΤΙ A. H3C-C-C-CH3 I (₁₁ +1)= 7 H CI B. H3C-C-CI H (3+1)=4 H LIH)=2 C. (CH3CH2-C-OH H D. CH3

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Q1: Draw the most stable and the least stable Newman projections about the C2-C3 bond for each of the following isomers (A-C). Are the barriers to rotation identical for enantiomers A and B? How about the diastereomers (A versus C or B versus C)? H Br H Br (S) CH3 (R) CH3 H3C (S) H3C H Br Br H A C enantiomers H Br H Br (R) CH3 H3C (R) (S) CH3 H3C H Br Br H B D identical

2. Histamine (below structure) is a signal molecule involved in immune response and is a neurotransmitter. Histamine features imidazole ring which is an aromatic heterocycle. Please answer the following questions regarding Histamine. b a HN =N C NH2 a. Determine hybridization of each N atom (s, p, sp, sp², sp³, etc.) in histamine N-a hybridization: N-b hybridization: N-c hybridization: b. Determine what atomic orbitals (s, p, sp, sp², sp³, etc.) of the lone pair of each N atom resided in N-a hybridization: N-b hybridization: N-c hybridization:

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29. Use frontier orbital analysis (HOMO-LUMO interactions) to decide whether the following dimerization is 1) thermally allowed or forbidden and 2) photochemically allowed or forbidden. +

30.0 mL of 0.10 mol/L iron sulfate and 20.0 mL of 0.05 mol/L of silver nitrate solutions are mixed together. Justify if any precipitate would form

Does the carbonyl group first react with the ethylene glycol, in an intermolecular reaction, or  with the end alcohol, in an intramolecular reaction, to form a hemiacetal?  Why does it react with the alcohol it does first rather than the other one?  Please do not use an AI answer.

The number of noncyclic isomers that have the composition C4H8Owith the O as part of an OH group, counting a pair of stereoisomers as1, is A. 8; B. 6; C. 9; D. 5; E. None of the other answers is correct.