Question

Consider the following data on some weak acids and weak bases: acid base name formula name formula nitrous acid HNO2 4.5*10-4 HCN 4.9x10-10 aniline CH-NH2 || 4.3 × 10 10 hydroxylamine HONH, 1.1 * 10-8 hydrocyanic acid Use this data to rank the following solutions in order of increasing pH. In other words, select a 'l' next to the solution that will have the lowest pH, a '2' next to the solution that will have the next lowest pH, and so on. solution PH 0.1 M C6H5NH3Br choose one 0.1 M NaCN choose one 0.1 M KNO2 choose one 0.1 M NaBr choose one

Answer 1

oil 2 ka= 1'0x1054 4.3x10-10 = 2.32x105 1) CGHSN by Br - CGHSN z & Bio Ca H5NH3 + Họ• CHỊNH, HỢP initial +x + change Cool-x) equilibrium ka= [Colts NH2] [48] Ka.kb = 1.0x1614 1. [CGHS No 2132*10% = ) = x=0.0015M pH = -log(0.0015) — 2.82 2) Nach Na + CN CNO + 40 - HON+ OH | Karkb= 10x10th Kb = 10x10 = 2.0bxios (0.1-x) = * = 0.0014 m pOH = -log(0.0014) → 2.85 ; pH+ POH = pH = 14-2.85 3) KNO, K't Nood Ng THO = HNQ + otº ka.kb = 1.0x16"* - >2.22x10" 2.22210" = ) **= 1.49 x 176m poh = tog (149x106) 5.83, PH+ POH= 14 → PH= 14-5.83 x2 2.04x105 4.981010 = 11.15 4.5x154 = 8:17 A) NaBr It is a salt of strong acid and strong base. It has a pH of 7. Increasing pH order of the solutions: C6H5NH₂Br < NaBr < KNO, < Nach pH value= 2182 7 8.17 11.15