1. Rank the alanes below in order of increasing relative Lewis acidity (1 is most acidic, 4 is least acidic). Provide a brief explanation for your ordering. AlCl3 Al(Et)3 Rank: AICI(Et)2 AlCl2(Et)

19.39 (a) Rank the following compounds in order of increasing acidity. (b) Which compound forms the strongest conjugate base? O₂N. OH A B OH C OH D OH

The following compound is being tested by Pfizer a drug candidate to treat Covid-19. There are multiple amide bonds in the structure that provide rigidity. There is another carbon that has the same oxidation state as a carboxylic acid derivative. Which carbon is it? F3C -NH HN PF-07321332 Selected Coordinates Clear

27(c) Most basic nitrogen A or B? (Hint: The lone pairs on the two play different roles in the aromaticity of the molecule, and consequently one Nitrogen will get protonated before the other)

Dd.22.

Suppose you have a mixture of these three compounds. Devise a chemical procedure based on their relative acidity or basicity to separate and isolate each in pure form.

As far back as the 16th century, South American Incas chewed the leaves of the coca bush, Erythroxylon coca, to combat fatigue. Chemical studies of Erythroxylon coca by Friedrich Wöhler in 1862 resulted in the discovery of cocaine, C17H21NO4, as the active component. Basic hydrolysis of cocaine leads to methanol, benzoic acid, and another compound called ecgonine, C9H15NO3. Oxidation of ecgonine with CrO3 yields a keto acid that readily loses CO2 on heating, giving tropinone. (a) What is a likely structure for the keto acid? (b) What is a likely structure for ecgonine, neglecting stereochemistry? (c) What is a likely structure for cocaine, neglecting stereochemistry?

The pKa, of the conjugate acid of morpholine is 8.33. (a) Calculate the ratio of morpholine to morpholinium ion in aqueous solution at pH 7.0. (b) At what pH are the concentrations of morpholine and morpholinium ion equal?

22. Which of the following is FALSE with regard to acid strength? A) B) C) D) E) HCIO3 > HCIO₂ H₂SO3 > H3PO3 HBr > H₂S H₂O > NH3 HF > HI

Given the Ka values (in parentheses) for the following acids: HSO4– (Ka= 1.2 x 10–2); HNO2 (Ka= 4.0 x 10–4); HC2H3O2 (Ka= 1.8 x 10–5); Calculate Kc values for the following acid-base equilibria: (a) HSO4–(aq) + C2H3O2–(aq) ⇌ HC2H3O2(aq) + SO42–(aq) (b) HC2H3O2(aq) + NO2–(aq) ⇌ HNO2(aq)+ C2H3O2–(aq)