acetylide

Sometimes a yellowish red precipitate is produced in solutions of copper salts containing free acid, but the deposit is not copper acetylide, and is more likely to be, at least in part, a copper phosphide -- especially if the gas is crude.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

Cuprous carbide or acetylide is the reddish brown amorphous precipitate which is the ultimate product obtained when acetylene is led into an ammoniacal solution of cuprous chloride.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

The objection is not sound, because the acetylide is not likely to be produced except in the presence of ammonia; and since frankoline is a highly acid product, the ammonia is converted into its chloride before any copper acetylide can be produced.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

Freund and Mai have also observed that when copper acetylide which has been dried in contact with air for four or five hours at a temperature of 50° or 60° C. is allowed to explode in the presence of a current of acetylene, an explosion accompanied by light takes place; but it is always local and is not communicated to the gas, whether the latter is crude or pure.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

Cuprous carbide, however, is very unstable and prone to oxidation; so that, given the opportunity, it combines with oxygen or hydrogen, or both, until it produces the copper acetylide, or acetylene-copper, which is explosive -- a body to which Blochmann's formula

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

For instance, Mai has found that freshly made copper acetylide can be heated to 60° C. or higher without explosion; but that if the compound is exposed to air for a few hours it explodes on warming, while if warmed with oxygen it explodes on contact with acetylene.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

Chapter VI. that the use of metallic copper in the construction of acetylene apparatus is not permissible or judicious, because the gas is liable to form therewith an explosive compound known as copper acetylide; it might seem, therefore, that the employment of a copper salt for purification courts accident.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

Caro has found that when pure dry acetylene is led for nine months over sheets or filings of copper, brass containing 63.2 per cent. of copper, red brass containing 73.8 per cent., so-called "alpaca-metal" containing 65.3 per cent., and britannia metal containing 90.2 per cent. of copper, no action whatever takes place at ordinary temperatures; if the gas is moist very small quantities of copper acetylide are produced in six months, whatever metal is tested, but the yield does not increase appreciably afterwards.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

His conclusions are that a copper acetylide is always produced if impure acetylene is allowed to pass through neutral or ammoniacal solutions of copper; that dry acetylene containing all its natural impurities except ammonia acts to an equal extent on copper and its alloys, yielding the explosive compound; that pure and dry gas does not act upon copper or its alloys, although it is possible that an explosive compound may be produced after a great length of time.

Acetylene, the Principles of Its Generation and Use W. J. Atkinson Butterfield

Theoretical Study on Photophysical Properties of Angular-Shaped Mercury (II) Bis (acetylide)

Gaea Times (by Simple Thoughts) Breaking News and incisive views 24/7 2009