Safety data for acetylene
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Risk phrases
Safety phrases
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for it. General
Synonyms: ethyne
Molecular formula: C2H2
CAS No: 74-86-2
EINECS No: 200-816-9
Annex I Index No: 601-015-00-0
Physical data
Appearance: Colourless gas with garlic-like ordour
Melting point: -80.8 C
Boiling point: -84 C (sublimes)
Critical temperature 35 C
Specific gravity: 0.9
Vapour pressure: 44 bar at 20 C
Flash point:
Explosion limits: 2.4 - 88% in air
Autoignition temperature: 325 F
Water solubility: 1.185 g/l
Stability
Stable. Extremely flammable. Readily forms explosive
mixtures with air. Even small amounts of acetylene/air
mixtures (for example a balloon the size of a grapefruit) can produce
damaging explosions if the mix is close
to stoichiometric. Therefore acetylene/air explosions, if carried out
as part of a chemistry show or a classroom demonstration,
should be approached with extreme caution.
Toxicology
No known toxic effects.
(The meaning of any risk phrases which appear in this section is
given
here.)
R5 R6 R12.
Transport information
(The meaning of any UN hazard codes which appear in this section
is given
here.)
UN No 1001. Hazard class 2.1.
Personal protection
Safety glasses. Good ventilation. Use ear protection if
doing an acetylene/air explosion as a demonstration and take appropriate precautions
to prevent harm to your audience!
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(The meaning of any safety phrases which appear in this section
is given here.)
S9 S16 S33.