The first to go would be chlorine gas, then the carbonate products.

FORBES: Magazine Article

It heard that when police raided Mr Railton's home last October he was found to have 98 different chemicals, including some that could make chlorine gas.

BBC: Man denies 'planned poison attack on bus' in Surrey

The jury was told that when police raided his home last October he was found to have 98 different chemicals, including some that could make chlorine gas.

BBC: Man 'planned poison attack on bus' in Surrey

Chlorine gas was used by both sides during World War I but was banned by the Geneva Protocol, along with the use of other poison gases, after the end of the war.

CNN: Al Qaeda's track record with chemical weapons

Letter dated March 28, 2007, showing the author's alarm at al Qaeda in Iraq's conduct (PDF) The author, who appears to be of Egyptian origin, asks a legal scholar about the use of chlorine gas.

CNN: The Osama bin Laden documents

The chlorine gas is captured and sold.

FORBES: Magazine Article

New Jersey is the most densely populated state in the country and on this particular two miles of land there are hundreds of potential terrorist targets including chemical plants, chlorine gas plants, rail yards, rail lines, refineries, an international airport, and the third largest port in the country.

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Chlorine is volatized in hot water meaning it turns into a gas that you then breathe.

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Neutrinos react with chlorine in the fluid and change it to radioactive argon, a gas.

ECONOMIST: Particle physics