Unit+11-+Acids+&+Bases

ACIDS AND BASES



The document above contains and outline and notes of acids and bases. Below are some added tips and notes.

Titration steps to remember 1) write balanced equation 2) "of" means to multiply 3) write your units so they match the end units you want ( i.e. if you want liters of HCl M bottom write them there!) 4) start the problem with the chem. your getting rid of

Equations to remember: 1) Kq= x2 divided by (1.00-x) 2) pH =pOH = 14 3) pOH=-log [OH-] 4)pH=-log[H+] Brackets means molarity (mols per liter) 5)10^-pH = [H+]

1) What is the pH of a 0.20 M HCl solution? A. < 0 B. 0.70-correct answer. Hint: use the pH formula above. C. 1.61 D. 12.39 E. 13.30 2) What is the [OH-] for a solution at 25°C that has [H3O+] = 2.35 × 10-3 M? A. 4.26 × 10-5 M B. 2.35 × 10-11 M C. 4.26 × 10-12 M-correct answer. Hint [H30+] x [OH-]=10x-14 D. 2.35 × 10-17 M E. none of these choices is correct 3) What is the [OH-] for a solution at 25°C that has pH = 4.29? A. 1.4 × 10-2 M B. 5.l × 10-5 M C. 1.9 × 10-10 M-correct answer. Hint: pOH +pH=14. pOH=-log[OH-] might need the inverse of log on your calculator. D. 7.3 × 10-13 M E. 9.71 M 4) What is the [H3O+] for a solution at 25°C that has pOH = 5.640? A. 2.34 × 10-4 M B. 2.29 × 10-6 M C. 4.37 × 10-9 M-correct answer. Hint: similar to last problem D. 4.27 × 10-11 M E. 8.360 M 5) Select the pair of substances in which an acid is listed followed by its conjugate base. A. H+, HCl B. NH3, NH4+ C. HPO42-, H2PO4- D. HCO3-, CO32-correct answer. E. CH3COOH, CH3COOH2+ 6) Select the pair of substances which is not a conjugate acid-base pair. A. H3O+, H2O B. HNO2, NO2- C. H2SO4, HSO4- D. H2S, S2-correct answer E. NH3, NH2- 7) According to Brønsted and Lowry, which one of the following is not a conjugate acid-base pair? A. H3O+/OH-correct answer. B. CH3OH2+/CH3OH C. HI/I-. D. HSO4-/SO42- E. H2/H- 8) A 0.050 M solution of the weak acid HA has [H3O+] = 3.77 × 10-4 M. What is the Ka for the acid? A. 7.5 × 10-3 M B. 2.8 × 10-6 M-correct answer. [H30+] is the x in the equation. C. 7.0 × 10-7 M D. 7.0 × 10-8 M E. 2.6 × 10-11 M