RyanJ

Umm... they don't. All cells reproduce so many times and then die otherwise peopel would live forver The first cell reproduces x times and then dies, the x daughter cells then reproduce x more times untill each of those die untill they all end up dead but no-one ever lives that long Cheers, Ryan Jones

Did YT write those or was he in them, in either case ! I would never question YT anyway, he knows his stuff in this fiend with no doubts Cheers, Ryan Jones

Ah, right! thanks YT! Onto the next quesiton I have - what type of Firefowk effects cna you have? I know thinkgs like Flash-Bang, Flash, etc but are there any more exptic type results? Also, this is more of a general question than a chemistry one but how do they make thoser fireworks that produce patterns when thy explode? Those thigns are really impressive! Cheers, Ryan Jones

You could with some complex VBA macros Cheers, Ryan Jones

Nice job Cheers, Ryan Jones

Do rockets use a flash-bang mixture? They shoot up rapidly then explode, this suggests some sort of flash powder or maybe a custom gunpowder mix? How do they know how long the reaction will take to complete? Is there a formual that allows one to work that out? Cheers, Ryan Jones

You could try columns, a able or something like that if you can work out hwo to do any of the above they should be close to what your looking for! (Table would probably be the best). I can't really give you exact instructions because I use OpenOffice.org Cheers, Ryan Jones

I'll start the thread then! First here are some of the oxidisers used in fireworks: [ce]NaNO3[/ce] - Sodium Nitrate [ce]KNO3[/ce] - Potassium Nitrate [ce]KClO3[/ce] - Potassium Chlorate [ce]KClO4[/ce] - Potassium Perchlorate [ce]KMnO4[/ce] - Potassium Permanganate There are others too, will add them as I collect then A question related to the above list. Can soemone explain why these are so good as oxidisers? Also, seeing as the other thread was deleted I'll ask this again so someone can reply (Woelen probably ): Wht makes the green colour in fireworks? I know white is commonly magnesium or sometimes aluminium but I have no idea what green is Cheers, Ryan Jones Edit: Fixed some chemical errors

The chemistry of pyrotechnics? I've always been interested in fire and fireworks as I know a lot of other people are, I think this is what actually sparked (HaHaHa, spark ignites explosives...) my interest in chemistry. I would also like to show through this thread that people are sensible with their knowledge and chemists is a bomb-crazed maniacs! So I was thinking about a thread related to pyrochemistry and let me state before we start this is not a thread related to the making of any explosive / pyrotechnic devices just a discussion on how they came to the recipes (Not actually positing them) and related subjects. I was thinking we could talk about: Why xxx is used in firework production - Pretty obvious. The chemistry of pyrotechnics - Why do these work the way they do, what are the reactions that go on in the centre of those fireworks? Calculations to do with the above - How would you calculate the blast radius of an explosion from 20g of TNT? Mathematical representations of the above points. How much energy is released when 20g of TNT is detonated? Why are things explosive - Why does Ammonium Triiodide explode and why is it so unstable? Why are some of these so unpredicatable? Why do fireworks work? - From a chemistry, mathematical or physics aspect! No money rubbish here please, we are scientists not bankers Hazards related to fireworks / explosives - Do all those metals used in Fireworks damage peoples health? Do they disrupt radio signals to phones in long term? Do they build up in the soil and air? Thread Rules: Read this thread before you post here! No discussion as to the making of explosive/pyrotechnic devices in any way shape or form. This includes links to other websites with the information! Discussion of the chemicals are permitted within reason. The methods of production must not be posted. No discussion of any prohibited chemicals and or devices (production etc.) This includes links to other websites with the information. Formulas may be posts as long as they don't relate to the production of the substance in question. Chemistry, mathematical and physics aspects only (general science). Keep to the forum TOS at ALL times! So the general rule is you can post anyhting as long as it does not tell people how to make the chemical in question or a device used to deploy it. And let me state again this is not a thread about making these devices, this thread would be good as long as it is kept on topic and away from the areas prohibited by the TOS as was intended by me I don't see why this topic would be banned as long as the people in this thread are responsible with that they say and post. A lot of people should be interested in this thread for the chemistry aspects so let me just say that if this is not acceptable to the moderators then please remove it is this thread is acceptable to the mods then if you have any more rules please add them! A warning from woelen:

Did I miss that bit? OOps... Looks like I did your right, that is the main part of it but being further from te center of the Earth also has an effect Cheers, Ryan Jones

I wish I did but thank you anyway Cheers, Ryan Jones

1) Yes it is hot but due to the increased preassure it is not high enough to melt the metal 2) Yes higher height equals lower preassure due to the fact its further from the center of the Earth Cheers, Ryan Jones

I'll leave this to the physics experts to explain. I can explain it to my self but when it comes to soemone else I'm usless I 'm afraid. If your right then you'll just have to add the theory to the pile but the majority of the scientists already believe that the accelerating version is correct, I bet thay have already thought about what you've said. Cheers, Ryan Jones

I've seen threads like this on other forums, there is gravity at the center of the Earth and the center of the Earth is solid! Links: http://www.scienceforums.net/forums/showthread.php?t=15792 http://www.scienceforums.net/forums/showthread.php?t=7174 http://www.newton.dep.anl.gov/askasci/env99/env002.htm Ryan Jones

Yes but its not, your method does not explain how things appear to be expanding faster now and how they could not have gotten to the current position by any method other than constant acceleration. Your theory is an interesting one but it lacks support for the facts, mainly things are moving away faster on all points... as you have said it has not been proven but it is accepted by all good scientists because it exactly matches the facts and observations that we have today. Brian does talk about the opposition in his book and how the scientifsts eventually came to the same conclusions as the theory and thats why its now accepted. Science is riggerous, don't you think if you were right they'd alredy have found and accepted what ou were saying? Cheers, Ryan Jones

If anything gravity increases preassure due to the fact your approching the center of gravity and have more mass being pulled twards you. You can't argue with facts, it is proven that the center of the Earth is solid by earthquake seismology (And the studdy of wave propegation through the Earth). Cheers, Ryan Jones

Firstly welcome to the forums!