maverick - 31-1-2006 at 10:43
Hai,
I'm new member.Stumbled onto one your posts during a searsh for the following .Well ,i need help with rapidly generating gasses through chemical
reactions.Commonly available reagents would be the best.The product may be any gas that is not a problem ,but preferably not a toxic one 
.Waiting for replies...
woelen - 31-1-2006 at 10:58
Take baking soda, a.k.a. sodium bicarbonate, NaHCO3. You can purchase that at any drugstore. Do not use baking powder, with all kinds of additives,
get the pure sodium bicarbonate.
Add dilute hydrochloric acid (10% HCl) to this and you'll get an instant violent reaction in which a LOT of carbon dioxide is formed. Non-toxic, no
hot reaction, immediate and simple. The only thing is that the reaction can be so fast, that the entire foaming liquid is swirled out of the container
(I had that once). The gas is colorless.
Another reaction, using bleach powder for swimming pools (calcium hypochlorite, e.g. HTH pool chlorine) can also be used in combination with 10% HCl.
That gives an equally fast reaction, but now you get a green gas. This reaction also is simple, not hot, and it is fast. BEWARE WITH THIS. THE GAS
LOOKS NEAT, BUT IT IS A DEADLY POISON IF INHALED, EVEN IN VERY SMALL DOSES. Only do this outside on a windy day, with the wind from behind. I mention
this reaction, not to encourage you that you do it, but as a warning. It is as simple as the reaction with sodium bicarbonate, but much more
dangerous, and that is why I tell you about it. Just in case that you stumble across it on the Internet.
neutrino - 1-2-2006 at 08:41
This page should help you:
Microscale Gas Chemistry
LiveWire - 2-2-2006 at 05:02
If you just want some gas, dump some baking soda into some vinegar.. No need to get fancy with HCl, and who cares if the baking soda isn't pure? You
can also just heat the baking soda, it releases the same carbon dioxide.
Another simple way is to use dry ice.. It slowly sublimes into carbon dioxide gas. If you want it to happen fast, dump some into water.
DeAdFX - 2-2-2006 at 17:37
Dont forget sodium acetate and Sodium hydroxide...
CH3COONa + NaOH --> CH4 + Na2CO3
CH4 + 2H2O --> CO2 + 4H2
This reaction needs a lot of heat and other certain conditions to occur. See steam reforming...
[Edited on 3-2-2006 by DeAdFX]
guy - 2-2-2006 at 18:09
If you want lots of hydrogen gas, use warm sodium hydroxide solution and aluminum foil. Hydrogen gas should be coming out pretty fast.
2Al + 2NaOH- + 6H2O ---> 3H2 + 2Na[Al(OH)4]
kazaa81 - 5-3-2006 at 11:17
2 Al + 6 HCl --> 3 H2 + 2 AlCl3 (very fast reaction, local over-ebullition often occur)
NaClO + HCl (any strong acid does) ---> Cl2 (warning, Cl2 is poisonous)
2 NaCl + H2SO4 --> 2 HCl + Na2SO4 (warning, HCl is poisonous and corrosive)
There is too a reaction between NH3, NaClO and H2O2 I've made a while ago (produced N2), but I can't remember it.
Have fun with gases!
HCl gas
Flip - 5-3-2006 at 11:35
Sulphuric acid and rock salt is always fun. Produces HCl gas. Wreaks havoc on your lungs and ruins your clothing, but it's always good fun.
mantis - 5-3-2006 at 11:58
instead of H2SO4 you can use NaHSO4, but you have to heat.