zstairlessone
iPF Novice
There is a beautiful picture on the images thread about an incredibly nasty reaction that humans have learned to elicit out of the elements. A little background:
Albert Einstein wrote a little formula with earth shattering (pun intended) results - E=MC^2 (energy equals mass times the speed of light squared). Generally this is used to show relativistic effects on particles as they are accelerated closer and closer to the speed of light, but it has another use, finding the energy released during fusion and fission events.
Because the picture was of a Hydrogen (or fusion) bomb, we will look at the fusion reaction. Fusion (named so because we are 'fusing' Hydrogen atoms together to form Helium) takes place by using 4 Hydrogen atoms to make one Helium atom. Now this sounds simple and all, but where does all the 'boom' and 'bang' come from? Quick answer - a hydrogen atom weighs roughly 1.67368 x 10^-27 kg while one Helium atom weighs in at a svelte 6.6463 x 10^-27 kg. I call this svelte because, as some may have noticed, this is less than the weight of the 4 Hydrogen atoms that we used to make our party balloon lifting atom. In fact the difference is 0.04872 x 10^-27 kg per Helium atom produced. What happened to the missing mass? Well, remember Einstein's formula? Let's look at it and see what we can find, ( along with a few other principles we need to make this work). We know that a mole of something is the number of atoms that make up the atomic weight in grams and this is 6.02 x 10^23 atoms. So a mole of hydrogen atoms (that big number is how many we are talking about) weighs in at just over one gram. Let's, for the sake of discussion, say that we have 2 kilograms of Hydrogen for making Helium, this means we have 2 x 1000 (grams per kilogram and 2 kilos) x 6.02 x 10^23 Hydrogen atoms in a mole and we get roughly 1.204 x 10^27 Hydrogen atoms for the process. Now we have the mass defect (number of hydrogen atoms divided by 4 times the missing mass for each helium) and we get a missing mass of 0.1457442 grams. This may not sound like much, but it is. Just how can less than 2 tenths of a gram mean much? E=MC^2
Now I have energy equals 0.1457442 grams times the speed of light SQUARED which gives the energy produced. C equals 299792458 meters per second, squared this becomes 8.988 x 10^16 which when multiplied by the missing weight is 1.309 x 10^16 or just over 31 BILLION kilocalories (a heck of a lot of heat) - hence the beautiful, but devastating fireball we see as a mushroom cloud.
Albert Einstein wrote a little formula with earth shattering (pun intended) results - E=MC^2 (energy equals mass times the speed of light squared). Generally this is used to show relativistic effects on particles as they are accelerated closer and closer to the speed of light, but it has another use, finding the energy released during fusion and fission events.
Because the picture was of a Hydrogen (or fusion) bomb, we will look at the fusion reaction. Fusion (named so because we are 'fusing' Hydrogen atoms together to form Helium) takes place by using 4 Hydrogen atoms to make one Helium atom. Now this sounds simple and all, but where does all the 'boom' and 'bang' come from? Quick answer - a hydrogen atom weighs roughly 1.67368 x 10^-27 kg while one Helium atom weighs in at a svelte 6.6463 x 10^-27 kg. I call this svelte because, as some may have noticed, this is less than the weight of the 4 Hydrogen atoms that we used to make our party balloon lifting atom. In fact the difference is 0.04872 x 10^-27 kg per Helium atom produced. What happened to the missing mass? Well, remember Einstein's formula? Let's look at it and see what we can find, ( along with a few other principles we need to make this work). We know that a mole of something is the number of atoms that make up the atomic weight in grams and this is 6.02 x 10^23 atoms. So a mole of hydrogen atoms (that big number is how many we are talking about) weighs in at just over one gram. Let's, for the sake of discussion, say that we have 2 kilograms of Hydrogen for making Helium, this means we have 2 x 1000 (grams per kilogram and 2 kilos) x 6.02 x 10^23 Hydrogen atoms in a mole and we get roughly 1.204 x 10^27 Hydrogen atoms for the process. Now we have the mass defect (number of hydrogen atoms divided by 4 times the missing mass for each helium) and we get a missing mass of 0.1457442 grams. This may not sound like much, but it is. Just how can less than 2 tenths of a gram mean much? E=MC^2
Now I have energy equals 0.1457442 grams times the speed of light SQUARED which gives the energy produced. C equals 299792458 meters per second, squared this becomes 8.988 x 10^16 which when multiplied by the missing weight is 1.309 x 10^16 or just over 31 BILLION kilocalories (a heck of a lot of heat) - hence the beautiful, but devastating fireball we see as a mushroom cloud.
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