Loved it!
Well I really enjoyed that! Nice to see such an innovative game and tying it in with atoms and crap is always interesting to see. =P
Once you get the hang of it, this game actually becomes pretty easy. You just have to follow these simple fundamental rules:
1) try to make your opponent the one who makes the particle unstable so in the central areas, the ideal situation is that you have a 7 and force him to press an unstable 8 which then allows you to ignite the blast effect in your favor [at the borders you want a 4 and at the edges you want a 2]
Therefore, with that idea in mind:
2) at the borders: try to keep your particle size as an odd number
3) in the middle: try to keep your particle size as an even number
4) and then from there just watch out for those chain reactions
the keys to success! :P
keep making games like these!