Kb (NH3) = 2*10^-5

==> NH3 + H(+) = NH4(+)

[ ]-square brackets = molar concentration  mol/l

 [NH4(+)] = 2*10^-5 * [NH3]

==> [NH3] >>> [NH4(+)]

Ka Cl-CH2-COOH ~ 1*10^-2

Cl-CH2-COOH <==> Cl-CH2-COO(-) + H(+)

[Cl-CH2-COO(-)]<<[Cl-CH2-COOH]

Cl-CH2-COO(-) + NH4(+) <==> Cl-CH2-COONH4 (Salt)

speed of this reaction = k1[RCOO(-)][NH4(+)]

Cl-CH2-COOH + NH3 = NH2-CH2-COOH + HCl <==>(NH3(+)-CH2-COOH)Cl(-)

Sn2 reaction==> speed = k2[Cl-CH2-COOH][NH3]

If k1 > 10^7 k2 ==>both reactions goes with some speed

but more realistic version that speed of reaction2 >> speed of reaction1

==> NH2-CH2-COOH will be formed faster

==>NH2-CH2-COOH

Experimentally "...прилейте раствор HCl, затем обработайте щелочью, если образовывалась соль аммония, то выделится аммиак..."

Cl-CH2-COONH4 + HCl = Cl-CH2-COOH + NH4Cl

NH4Cl + OH(-) = NH3 + H2O + Cl(-)

NH2-CH2-COOH + HCl = (NH3(+)-CH2-COOH)Cl(-)

(NH3(+)-CH2-COOH)Cl(-) + OH(-) = NH2-CH2-COOH + H2O + Cl(-)