Determine (a) the velocity of a Ne atom that has Ek = 1.12 × 10-20 J, (b) the velocity of a Kr atom that has Ek = 1.12 × 10-20 J. (c) the mass and identity of an atom moving at 315 m/s that has Ek = 3.704 × 10-20 J.
Chapter 15 — Applications of Aqueous Equilibria 1 I. Acid / Base Titration Calculations: A. strong acid with strong base, pH at equivalence point = 7 B. strong acid with weak base, pH at equivalence point < 7 weak acid with strong base, pH at equivalence point > 7 C. D. weak acid with weak base, pH at equivalence point that depends on K , Ka b II. acid—base indicator — weak acid having one color and the conjugate base having a different color A. used in application in which precise pH readings are not necessary III.Common Ion Effect — suppression of the ionization of a weak acid or base by the presence of its conjugate base or acid A. CH C3 H 2 CH CO ,3NH &2NH 3 4 B. controlling pH using buffer solutions: 1. buffer — solution that changes pH only slightly when small amounts of a strong acid or a strong base are added; weak acid and its conjugate base 2. buffer capacity — measure of the amount of acid or base that a buffer solution can absorb without signiﬁcant change in pH can also be represented by how little the pH changes with addition of a given a) amount of acid or base b) depends on the number of moles of weak acid and conjugate base that are present C. Henderson—Hasselbalch Equation: 1. a 2[H O ] = K [Acid] pH = pK + log [conjugate base] 3. a a [Base] a [weak acid] 4. a IV. solubility product constant, sp, is based on n+saturay—d aqueous solution A. for dissolution process M m x m M + x X : 1. K sp= [M n+] [X y— ] B. how to measure K : prepare a saturated solution of the compound 1. 2. add excess solid to the solution (solution will reach equilibrium containing maximum concentration of dissolved ions) 3. measure ion concentration at equilibrium and plug into K spexpression V. precipitation of ionic compounds A. Q sp is the ion product reaction quotient and is based on initial conditions of the reaction B. precipitation will occur ifsp> K sp C. precipitation cannot occur if Qsp< K sp D. solution is just saturated ifsp= K sp