Question

6-47. Which is a stronger acid, (a) or (b)? (a) o (b) loro СІ,НССОН СІН,ССОН Dichloroacetic acid Chloroacetic acid K = 8 X 10-2 K = 1.36 X 10-3 Which is a stronger base, (c) or (d)? (c) HANNH2 (d) Hydrazine K = 1.1 x 10" o H2NCNH2 Urea K = 1.5 X 10-14

Answer 1

H₂ c cot Cl₂ HCC oH Dichloroacetic and ka=8610-2 chloroacetic and Ka 1.36x103 enclo 2010 von More stronger -4 4-C=0 -2-o# =HT Dott@ less Stronger tu . Hc- çao # 19 Acids are that compound, which donates H® in solution. Here, both and are arid but Dichloro acetic acid is more stronger and than chloro acetic acid. Due to the electronegatie effect ofd Dichtoro ahlthdraw more electron density in from the o-H group than a single chlorine atom. Therefore it donates ion than B. so pka of ④ is smaller thom ,

4N- NH₂ Vrea H₂N-NH₂ Hydrazine Kb= 1.1x10-6 K6=15x10-14 Lewis bases are those, which donates electron density. In and 6 both have electron density property due to presence of Nith group. In Hydratine, the lone pair of nitrogen atom (W) is easily available for donation but in urea the lone pair of nitrogens are in conjugation with the cartony a group So, the lone pair in soot easily available in Case of urea. so, the basicity of Hydrazine is higher than urea.