Originally posted by mad scientist
An accidental explosion in a German physics lab has led to the identification of a superpowerful explosive. The substance - an exotic form
of silicon - releases seven times as much energy as TNT, and explodes a million times faster.
The authors of the article are illiterate about science.
Here is a quick lesson in basic chemistry:
The energy associated with an exothermic (heat releasing)
reaction has the dimensions of KJ/mole (kilo joules per mole).
For silicon and oxygen reacting to form silicon dioxide (sand)
the energy release is about 860 KJ/mole. For TNT exploding
the energy release is about 616 KJ/mole. Thus the energy
associated with making sand is little more that of exploding
TNT. Useful explosives must transfer their energy release into
mechanical work. They do this when hot expanding gases are
created by the energy release and cause an over pressure
condition in their surroundings, usually described as a shock
wave, that for example, can knock building walls down, or
"blow up" a bridge, and so on. Reacting silicon and oxygen
simply makes hot silicon dioxide. No expansion of gases. The
reason the reaction "exploded" in the experiment is because
some excess oxygen within the porous silicon was heated and
expanded. Otherwise it was just a form of "thermit" reaction..
that is heat releasing, with little effective explosive power.
It wasn't 7 times as "powerful", its' not an effective explosive,
and it doesn't "explode" a million times faster than TNT.
[edit on 1-11-2004 by mockan]