With no explanation, label each line with "O", "other-chemicalthing", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Common
syntheses
of
acyl
chlorides
also
entail
the
reaction
of
carboxylic
acids
with
phosgene
,
thionyl
chloride
,
and
phosphorus
trichloride
Phosphorus
pentabromide
is
used
for
acyl
bromides
,
which
are
rarely
of
value
.
Common:O
syntheses:O
of:O
acyl:other-chemicalthing
chlorides:other-chemicalthing
also:O
entail:O
the:O
reaction:O
of:O
carboxylic:other-chemicalthing
acids:other-chemicalthing
with:O
phosgene:other-chemicalthing
,:O
thionyl:other-chemicalthing
chloride:other-chemicalthing
,:O
and:O
phosphorus:other-chemicalthing
trichloride:other-chemicalthing
Phosphorus:other-chemicalthing
pentabromide:other-chemicalthing
is:O
used:O
for:O
acyl:other-chemicalthing
bromides:other-chemicalthing
,:O
which:O
are:O
rarely:O
of:O
value:O
.:O