27. Which is the strongest acid? A. acetic acid Ka = 1.8 x 10-5 %3D B. benzoic acid Ka = 6.3 x 10-s %3D - C. formic acid Ka = 1.8 x 104 %3D D. nitrous acid - Ka 6.0 x 104 %3D

1. The weak acid ammonium has the chemical formula NH4+. Write the balanced equation for NH4+ acting as a weak acid. 2. The weak acid ammonium has the chemical formula NH4+. The Ka value for ammonium is 5.6 x 10-10. Write the Ka expression for this reaction. 3. Hydrogen sulfite has the chemical formula HSO3-. Write the balanced equation for HSO3- acting as a weak acid. 4. Hydrogen sulfite has the chemical formula HSO3-. The Ka value for hydrogen sulfite is 6.2 x 10-8. Write the Ka expression for this reaction. 5. In a Ka expression, which term is always by itself in the denominator? 6. Place in order of increasing strength hydrogen sulfate, hydrofluoric acid, hydrochloric acid, ammonia, acetic acid, and hydrocyanic acid.

Which of the following weak acid solutions is the strongest acid? OK, = 7.89 x 10-12 %3D O Ka = 3.27 x 10-11 %3D O Ką = 6.7 x 10-9 %3D O K, = 2.94 x 10-6 %3D Ka = 5.42 x 10-6 %3D

Which of the following statement best explain why the acidity of carboxylic acids is greater than those of the alcohols? a. Alcohols behave as neutral compounds in aqueous solution. b. Alcohol has the ability to donate proton to becomes a negative ion called an alkoxide ion, RO– c. When a carboxylic acid donates its proton, it becomes a negatively charged ion, RCOO−, called a carboxylate ion which is more stabilized by resonance. d. The OH group in alcohol is less charged and often more difficult to release electron for chemical reactions.