pixels and nukes

[Bob Norton]

>In modern times it is also an animation technique. Pixel from the dots on 
>your CRT has a similar root. Pixies are small movable objects in computer 
>games.

Not really. Pixel is an abreviation for "picture element". 

>An Atom bomb relies on "splitting" hydrogen atoms, while a nuclear
explosion >is caused by the device reaching "critical mass."

An atom bomb works by splitting uranium or, more commonly, plutonium atoms.
You can't split an ordinary hydrogen atom, as its nucleus is a single
proton. You can fuse hydrogen,however, at least its dueterium and tritium
variants, which have respectively one and two neutrons in their nuclei,
creating helium isotopes, fast neutrons, and a really big bang.