9.6C: Reactions in Liquid NH₃
- Page ID
- 33837
Much of the chemistry in liquid ammonia can be classified by analogy with related reactions in aqueous solutions. Comparison of the physical properties of \(\ce{NH3}\) with those of water shows \(\ce{NH3}\) has the lower melting point, boiling point, density, viscosity, dielectric constant and electrical conductivity; this is due at least in part to the weaker hydrogen bonding in \(\ce{NH3}\) and because such bonding cannot form cross-linked networks, since each \(\ce{NH3}\) molecule has only one lone pair of electrons compared with two for each H2O molecule.
Solvolysis: synthesis of amides
\[\ce{ OPCl3 + 6NH3 -> OP(NH2)3 + 3NH4Cl}\]
\[\ce{SiCl4 + 8NH3 -> Si(NH2)4 + 4NH4Cl}\]
Metatheses reactions: solubility reversals
\[\ce{ RCl + AgNO3 ->[H2O] AgCl(s) + RNO3}\]
\[\ce{ AgCl + KNO3 ->[NH3] KCl(s) + AgNO3}\]
\[\ce{Ba(NO3)2 + 2AgCl ->[NH3] BaCl2(ppt) + 2AgNO3}\]
Sodamide as a base
\[\ce{ Na + NH3 -> NaNH2 + H2(g)}\]
\[\ce{NaNH2 + C5H6 -> NaC5H5 + NH3}\]
\(\ce{NaC_p}\) (useful reagent)