Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: Urza on 20/10/2011 00:47:25

Title: Could Sweat Ignite?
Post by: Urza on 20/10/2011 00:47:25

Could the sodium in body sweat react with oxygen if heated enough and ignite?

Title: Could Sweat Ignite?
Post by: damocles on 20/10/2011 04:05:26

No. All sodium in the body, and in sweat, is in the form of sodium ion, a very unreactive form of sodium. Sodium metal, a soft, yellowish metal that tarnishes rapidly in air and reacts violently with water, does not occur in nature, and certainly not in biological systems. It is a high energy form of the element, and a lot of electrical energy is required to produce it in special electrolysis cells. It could never exist in sweat, not even for microseconds, because it would react violently with it.

Title: Could Sweat Ignite?
Post by: Urza on 20/10/2011 05:39:54

But if you heated the sweat to over 100 degrees Celsius the water would evaporate, would some of the sodium vaporize as well, and would that sodium be able to ignite?

Title: Could Sweat Ignite?
Post by: damocles on 20/10/2011 05:59:09

No, because for every sodium ion (positive charge) there would be a matching negative ion, usually a chloride ion, and the residue after evaporation
would be sodium chloride (common salt), or, in smaller quantities, the sodium salt of one of a number of common organic acids. Sodium metal is definitely not a possibility.

Title: Could Sweat Ignite?
Post by: CliffordK on 20/10/2011 08:36:54

If, however, you had pure sodium metal, it might react violently with sweat. 

Note to self,
Never substitute sodium metal for underarm antiperspirant.   [:o]

Title: Could Sweat Ignite?
Post by: Geezer on 20/10/2011 08:47:30

Quote from: CliffordK on 20/10/2011 08:36:54

Note to self,
Never substitute metal for underarm antiperspirant.

Too late. Most of it is loaded with aluminum aluminium alumium, which is pretty reactive too.