Very carefully and always watching out for safety! This particular
pair, in their elemental form, are so dangerous I recommend that you do
not even try to obtain either pure sodium or pure chlorine by
themselves. For one thing, chlorine gas is extremely poisonous. It is
used to kill bacteria in water in very low concentrations, and it is
lethal to inhale the gas (it may even have been used in war to kill
soldiers before it was banned by the Geneva convention).
Sodium is very reactive with air and water (and most air has some
water in it!). Elemental sodium is usually stored in oil for this
reason. When exposed to water, it combines so rapidly, it glows bright
orange and may even explode. The explosion products include lye, NaOH,
which is toxic and corrosive. Don't mess with this one either.
Just putting one of the most reactive metals in the same jar as
one of the most reactive gases will almost certainly spontaneously
ignite and explode, leaving -- you guessed it, ho-hum table salt, NaCl,
which is perfectly safe, non-explosive, edible, and even necessary for
life!
You can buy table salt at the grocery store, and by stirring it in
water, you can separate the sodium ions from the choride ions, which
stick to water molecules. But don't try making any salt from scratch!
Salt comes ready-made from salt mines and by evaporating ocean water.
Tom
(published on 10/22/2007)