tonnes per year are used either directly or in combination. Major uses
are the manufacture of nitric acid,
ammonium nitrate, ammonium
phosphate, and urea (the last three as
fertilizers), explosives, dyestuffs and
resins.
Liquid ammonia has some similarity to water as it is hydrogen bonded
and has a moderate dielectric constant, which permits it to act as an
ionizing solvent. It is weakly selfionized to give ammonium ions,
NH 4
+ and amide ions, NH 2
– . It also
dissolves electropositive metals to
give blue solutions, which are believed to contain solvated electrons.
Ammonia is extremely soluble in
water giving basic solutions that contain solvated NH 3 molecules and
31
ammonia
a
H 2 C
H 2 C
N
H
H 2 C
*methionine
Met
M
CH 3
S
CH 2
COOH
NH 2
H
C
CH 2
CH 2
COOH
NH 2
H
C
*phenylalanine
Phe
F
proline
Pro
P
serine
Ser
S
*threonine
Thr
T
*tryptophan
Trp
W
*tyrosine
Tyr
Y
*valine
Val
V
*an essential amino acid
CH 2
CH COOH
CH 2
C
H
OH
CH COOH
N
H
4–hydroxyproline
NH 2
CH 2
HO
COOH
C
H
NH 2
COOH
C
H
CH
CH 3
OH
NH 2
CH 2
COOH
C
H
CH
N
H
C
HO
NH 2
CH 2
COOH
C
H
NH 2
CH
COOH
C
H
H 3 C
H 3 C
The amino acids occurring in proteins
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