The theory was Ünally demolished
by Antoine Lavoisier, who showed by
careful experiments with reactions
in closed containers that there was
no absolute gain in mass – the gain
in mass of the substance was
matched by a corresponding loss in
mass of the air used in combustion.
After experiments with Priestley’s dephlogisticated air, Lavoisier realized
that this gas, which he named oxygen, was taken up to form a calx
(now called an oxide). The role of
oxygen in the new theory was almost
exactly the opposite of phlogiston’s
role in the old. In combustion and
corrosion phlogiston was released; in
the modern theory, oxygen is taken
up to form an oxide.
phonochemistry The use of highfrequency sound (ultrasound, with a
frequency greater than about 20 kHz)
to induce or accelerate certain types
of chemical reaction.
phosgene See carbonyl chloride.
phosphagen A compound found
in animal tissues that provides a reserve of chemical energy in the form
of high-energy phosphate bonds. The
most common phosphagens are
creatine phosphate, occurring in vertebrate muscle and nerves, and arginine phosphate, found in most
invertebrates. During tissue activity
(e.g. muscle contraction) phosphagens give up their phosphate groups,
thereby generating *ATP from ADP.
The phosphagens are then reformed
when ATP is available.
phosphates Salts based formally
on phosphorus(V) oxoacids and in
particular salts of *phosphoric(V)
acid, H 3 PO 4 . A large number of polymeric phosphates also exist, containing P–O–P bridges. These are formed
by heating the free acid and its salts
under a variety of conditions; as well
as linear polyphosphates, cyclic
polyphosphates and cross-linked
polyphosphates or ultraphosphates
are known.
phosphatides See phospholipids.
phosphide A binary compound of
phosphorus with a more electropositive element. Phosphides show a
wide range of properties. Alkali and
alkaline earth metals form ionic
phosphides, such as Na 3 P and Ca 3 P 2 ,
which are readily hydrolysed by
water. The other transition-metal
phosphides are inert metallic-looking
solids with high melting points and
electrical conductivities.
phosphine A colourless highly
toxic gas, PH 3 ; m.p. –133°C; b.p.
–87.7°C; slightly soluble in water.
Phosphine may be prepared by reacting water or dilute acids with calcium phosphide or by reaction
between yellow phosphorus and concentrated alkali. Solutions of phosphine are neutral but phosphine
does react with some acids to give
phosphonium salts containing PH 4
+
ions, analogous to the ammonium
ions. Phosphine prepared in the laboratory is usually contaminated with
diphosphine and is spontaneously
Ûammable but the pure compound is
not so. Phosphine can function as a
ligand in binding to transition-metal
ions. Dilute gas mixtures of very pure
phosphine and the rare gases are
used for doping semiconductors.
phosphinic acid (hypophosphorus
acid) A white crystalline solid,
H 3 PO 2 ; r.d. 1.493; m.p. 26.5°C; decomposes above 130°C. It is soluble in
water, ethanol, and ethoxyethane.
Salts of phosphinic acid may be prepared by boiling white phosphorus
with the hydroxides of group I or
group II metals. The free acid is made
by the oxidation of phosphine with
iodine. It is a weak monobasic acid in
which it is the –O–H group that is
phonochemistry
410
p
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by Antoine Lavoisier, who showed by
careful experiments with reactions
in closed containers that there was
no absolute gain in mass – the gain
in mass of the substance was
matched by a corresponding loss in
mass of the air used in combustion.
After experiments with Priestley’s dephlogisticated air, Lavoisier realized
that this gas, which he named oxygen, was taken up to form a calx
(now called an oxide). The role of
oxygen in the new theory was almost
exactly the opposite of phlogiston’s
role in the old. In combustion and
corrosion phlogiston was released; in
the modern theory, oxygen is taken
up to form an oxide.
phonochemistry The use of highfrequency sound (ultrasound, with a
frequency greater than about 20 kHz)
to induce or accelerate certain types
of chemical reaction.
phosgene See carbonyl chloride.
phosphagen A compound found
in animal tissues that provides a reserve of chemical energy in the form
of high-energy phosphate bonds. The
most common phosphagens are
creatine phosphate, occurring in vertebrate muscle and nerves, and arginine phosphate, found in most
invertebrates. During tissue activity
(e.g. muscle contraction) phosphagens give up their phosphate groups,
thereby generating *ATP from ADP.
The phosphagens are then reformed
when ATP is available.
phosphates Salts based formally
on phosphorus(V) oxoacids and in
particular salts of *phosphoric(V)
acid, H 3 PO 4 . A large number of polymeric phosphates also exist, containing P–O–P bridges. These are formed
by heating the free acid and its salts
under a variety of conditions; as well
as linear polyphosphates, cyclic
polyphosphates and cross-linked
polyphosphates or ultraphosphates
are known.
phosphatides See phospholipids.
phosphide A binary compound of
phosphorus with a more electropositive element. Phosphides show a
wide range of properties. Alkali and
alkaline earth metals form ionic
phosphides, such as Na 3 P and Ca 3 P 2 ,
which are readily hydrolysed by
water. The other transition-metal
phosphides are inert metallic-looking
solids with high melting points and
electrical conductivities.
phosphine A colourless highly
toxic gas, PH 3 ; m.p. –133°C; b.p.
–87.7°C; slightly soluble in water.
Phosphine may be prepared by reacting water or dilute acids with calcium phosphide or by reaction
between yellow phosphorus and concentrated alkali. Solutions of phosphine are neutral but phosphine
does react with some acids to give
phosphonium salts containing PH 4
+
ions, analogous to the ammonium
ions. Phosphine prepared in the laboratory is usually contaminated with
diphosphine and is spontaneously
Ûammable but the pure compound is
not so. Phosphine can function as a
ligand in binding to transition-metal
ions. Dilute gas mixtures of very pure
phosphine and the rare gases are
used for doping semiconductors.
phosphinic acid (hypophosphorus
acid) A white crystalline solid,
H 3 PO 2 ; r.d. 1.493; m.p. 26.5°C; decomposes above 130°C. It is soluble in
water, ethanol, and ethoxyethane.
Salts of phosphinic acid may be prepared by boiling white phosphorus
with the hydroxides of group I or
group II metals. The free acid is made
by the oxidation of phosphine with
iodine. It is a weak monobasic acid in
which it is the –O–H group that is
phonochemistry
410
p
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