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Ammonia forms 1:1 adducts with a variety of Lewis acids such as I 2, phenol, and Al(CH 3) 3. Ammonia is a hard base (HSAB theory) and its E & C parameters are E B = 2.31 and C B = 2.04. Its relative donor strength toward a series of acids, versus other Lewis bases, can be illustrated by C-B plots.
Expressing resonance when drawing Lewis structures may be done either by drawing each of the possible resonance forms and placing double-headed arrows between them or by using dashed lines to represent the partial bonds (although the latter is a good representation of the resonance hybrid which is not, formally speaking, a Lewis structure).
The most common Lewis bases are anions. The strength of Lewis basicity correlates with the pK a of the parent acid: acids with high pK a 's give good Lewis bases. As usual, a weaker acid has a stronger conjugate base. Examples of Lewis bases based on the general definition of electron pair donor include: simple anions, such as H − and F −
Table data (above) obtained from CRC Handbook of Chemistry and Physics 44th ed. The (s) notation indicates equilibrium temperature of vapor over solid. Otherwise temperature is equilibrium of vapor over liquid. log 10 of anydrous ammonia vapor pressure. Uses formula shown below.
In aqueous solution, ammonia deprotonates a small fraction of the water to give ammonium and hydroxide according to the following equilibrium: . NH 3 + H 2 O ⇌ NH + 4 + OH −.. In a 1 M ammonia solution, about 0.42% of the ammonia is converted to ammonium, equivalent to pH = 11.63 because [NH +
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged molecular ion with the chemical formula NH + 4 or [NH 4] +.It is formed by the addition of a proton (a hydrogen nucleus) to ammonia (NH 3).
Ammonia borane (also systematically named ammoniotrihydroborate [citation needed]), also called borazane, is the chemical compound with the formula H 3 NBH 3.The colourless or white solid is the simplest molecular boron-nitrogen-hydride compound.
This name has been discarded as modern chemistry considers color less important than molecular structure. Other metal ammine complexes also were labeled according to their color, such as purpureo (Latin: purple) for a cobalt pentammine complex , and praseo (Greek: green) and violeo (Latin: violet) for two isomeric tetrammine complexes.