7. Coffee, though essential to a college student, is is the concentration of hydroxide ions in coffee? (Coffee's pH is 5) 8. Coke (the beverage) is highly acidic, with a pH of 2.7! Find the concentration of hydronium ion in 900 ml of Coca-Cola. H30*

Question 11

Ammonia is often used as a glass cleaner. Calculate hydronium concentration of a sample of ammonia that has a pOH of 3.600 You MUST show your work, and then record your final answer with the correct number of significant digits and proper units.

A. What is the pH of an aqueous solution with a hydrogen ion concentration of [H+]=7.2×10−5[H+]=7.2×10−5 M?   B. What is the hydroxide ion concentration, [OH−][OH−], in an aqueous solution with a hydrogen ion concentration of [H+]=7.2×10−5[H+]=7.2×10−5 M? C. A monoprotic weak acid, HAHA, dissociates in water according to the reaction HA(aq)↽−−⇀H+(aq)+A−(aq)HA(aq)↽−−⇀H+(aq)+A−(aq) The equilibrium concentrations of the reactants and products are [HA]=0.120 M[HA]=0.120 M, [H+]=3.00×10−4 M[H+]=3.00×10−4 M, and [A−]=3.00 ×10−4 M[A−]=3.00 ×10−4 M. Calculate the ?aKa value for the acid HA.

D Question 8 A solution has a hydrogen ion concentration measured by chemical means. It has a concentration of H+ 3.46 X 106. What is the pH value of the solution?

Each row of the table below describes an aqueous solution at about 25 °C. Complete the table. That is, fill in any missing entries in third column. Be sure each entry you write includes the correct number of significant digits. [1,0] solution pH -7 8.4 x 10 mol/L ? B 0.72 mol/L – 10 mol/L 4.1 x 10

12

- 14 + An aqueous solution at 25 °C has a OH concentration of 3.4 × 10 M. Calculate the H₂O* concentration. Be sure your answer has 2 significant digits. M Dx1 x10 Ś

6. The pH scale is a logarithmic scale. The acidity of a substance A is 2,000 times more acidic than a substance B with a pH of 6. What is the pH of substance A.

Identify the following as acids, bases or neutral solutions. a. Acidic [OH] = 3.5 x 10-2 b. Neutral (H30*) = 1.5 x 10-5 C. Basic pH = 12 [OH]= [H30*]