Chapter 3.7, Problem 27P

Write a net ionic equation to show that caffeine, C3H10N402, behaves as a Bronsted-Lowry base in water. BL base BL acid BL acid BL base + H2O +

Explain the difference in the solubility of benzoic acid and sodium benzoate in water.Which of the two would you predict to be more soluble in CHCl3? Explain.

1. Please illustrate the molecular structure of pyruvic acid, a weak acid. Identify the conjugate base of pyruvic acid. Given that the total concentration of pyruvic acid ( inclusive of both the weak acid and its conjugate base) in a red blood cell's cytoplasm is 0.051 M, determine the individual concentrations of the weak acid and conjugate base forms of pyruvic acid within a typical red blood cell. Consider the cytoplasm's pH of 7.4 and the acid dissociation constant (Ka) for pyruvic acid, which is 3.2 \ times 10^-3.

Using the table of the weak base below, you have chosen Pyridine as your weak base in the buffer solution. You have already added enough of the conjugate acid salt to make the buffer solution concentration at 0.62 M in this salt. The desired pH of the buffer should be equal to 4.5. Values of K, for Some Common Weak Bases Conjugate Acid Name Formula Ammonia Methylamine Ethylamine Aniline NH3 CH;NH2 CH;NH2 CH;NH, C;H;N NH,+ CH;NH;* CH$NH;* CH;NH;* C;H;NH* 1.8 × 10-5 4.38 x 10-4 5.6 x 10-4 3.8 x 10-10 1.7 x 10-9 Pyridine 3. Compute the concentration of the weak base in Molarity. (Write your answer in 3 decimal places without the unit).

Answer 1,2,3 and 4 or atleast the first three questions.

16-35 (Chemical Connections 16B ) What is an alkaloid? Are all alkaloids basic to litmus?

18-17 Hexanoic (caproic) acid has a solubility in water of about 1 g/100 mL water. Which part of the molecule contributes to water solubility, and which part prevents solubility?

Acid-Base Equilibria Many factors contribute to the acidity of organic compounds. Electronegativity, resonance, induction, hybridization, aromaticity, and atomic size, all play a role. In the following comparisons, you are asked to identify the factor(s) that would be most important to analyze when predicting relative acidity, and then to predict the trend in acidity and pKa values. For each of the following pairs of compounds answer the following two multiple-choice questions. 1. What factor(s) are the most important to consider when predicting the relative acidity of the two compounds? a. Electronegativity of the atom possessing the hydrogen. b. Resonance stabilization of the anionic conjugate base. c. Inductive stabilization of the anionic conjugate base. d. Hybridization of the atom possessing the hydrogen. e. The atomic size of the atom possessing the hydrogen.

11.27: Tell which is the stronger base and why? Aniline or p-cyanoaniline b) aniline or diphenylamine WH₂ |ال 11.30: Place the following substances, which have nearly identical formula weights, in order of increasing boiling point? 1-aminobutane, 1-butanol, methyl propyl ether, pentane