I like group I and group VII elements because of the violence and power of their reactions. For group VII elements, towards the lower reaches of the group, the relative atomic masses of the elements aren't much more than the element prior. And then you hit Iodine. It sits between Tellurium (RAM 127.6) and Xenon (RAM 131.3) so you'd think it would have a RAM of about 129, but it doesn't. It's *lower* than Tellurium. How can this be? And why?
The reason is that Iodine only really has one stable isotope (which is why its RAM is roughly equivalent to the number of nucleons; 127) whereas Tellurium has all kinds of stable isotopes and the most stable of all are the heaviest (128 and 130 nucleons).
This effect is almost like a subatomic seismic fault line. It says that something is going on. And something is. Most Chemistry students will know the following numbers mean something:
8, 20, 28, 50, 82, and 126
They're the number of electrons (and corresponding nuclear protons) in full energy shells. What's the element with most isotopes? Tin. And it's atomic number? 50. It's in the list. So what's the atomic number of Tellurium. 126. There it is in the list again. Full energy shells make for stable nuclei that can accomodate extra neutrons.
And all this flows from the fact that Iodine has a lower relative atomic mass than the supposedly less massive element before it.
This is why I'm choosing Iodine. From a freak result in relative atomic mass, a whole world reveals itself about the structure and stability of atoms. It's like a little door at the back of a wardrobe that is, when all said and done, just a little door. But on the other side of it is Narnia.
P.S. Interesting fact I was going to weave in but forgot to. Elements with even atomic numbers are more abundant than ones with odd, because they are more stable. Silver and Gold both have odd numbers. Iron is even.
That depends on how you look at it. Yes, eight out of ten of the most common elements in our galaxies have even atomic numbers. On the other hand, there's still more hydrogen in our galaxy (and probably in the universe) than all other elements combined, so if you picked an atom at random, it's most likely to have an odd atomic number.
I came SO close to responding to my own post for a second time just to mention Hydrogen and to say that the numbers are biased because it's the starting point elementally; that every other element in the universe was once Hydrogen in a star. I knew someone would say something if I didn't. :P
P.S. Still waiting for someone to say that Platinum has an even number, yet is roughly as rare as Gold.
What is your favorite element off of the periodic table?
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I like group I and group VII elements because of the violence and power of their reactions. For group VII elements, towards the lower reaches of the group, the relative atomic masses of the elements aren't much more than the element prior. And then you hit Iodine. It sits between Tellurium (RAM 127.6) and Xenon (RAM 131.3) so you'd think it would have a RAM of about 129, but it doesn't. It's *lower* than Tellurium. How can this be? And why?
The reason is that Iodine only really has one stable isotope (which is why its RAM is roughly equivalent to the number of nucleons; 127) whereas Tellurium has all kinds of stable isotopes and the most stable of all are the heaviest (128 and 130 nucleons).
This effect is almost like a subatomic seismic fault line. It says that something is going on. And something is. Most Chemistry students will know the following numbers mean something:
8, 20, 28, 50, 82, and 126
They're the number of electrons (and corresponding nuclear protons) in full energy shells. What's the element with most isotopes? Tin. And it's atomic number? 50. It's in the list. So what's the atomic number of Tellurium. 126. There it is in the list again. Full energy shells make for stable nuclei that can accomodate extra neutrons.
And all this flows from the fact that Iodine has a lower relative atomic mass than the supposedly less massive element before it.
This is why I'm choosing Iodine. From a freak result in relative atomic mass, a whole world reveals itself about the structure and stability of atoms. It's like a little door at the back of a wardrobe that is, when all said and done, just a little door. But on the other side of it is Narnia.
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VioletTrees
11 years ago
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dappled
11 years ago
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It's LIKE Narnia, but there are no Jesus lions.
P.S. Interesting fact I was going to weave in but forgot to. Elements with even atomic numbers are more abundant than ones with odd, because they are more stable. Silver and Gold both have odd numbers. Iron is even.
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Mrman10
11 years ago
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VioletTrees
11 years ago
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I was expecting you to respond :p
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dappled
11 years ago
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Heh! This kind of IIN question is like my Oxygen.
That depends on how you look at it. Yes, eight out of ten of the most common elements in our galaxies have even atomic numbers. On the other hand, there's still more hydrogen in our galaxy (and probably in the universe) than all other elements combined, so if you picked an atom at random, it's most likely to have an odd atomic number.
It works ok for elements found on Earth, though.
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dappled
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I came SO close to responding to my own post for a second time just to mention Hydrogen and to say that the numbers are biased because it's the starting point elementally; that every other element in the universe was once Hydrogen in a star. I knew someone would say something if I didn't. :P
P.S. Still waiting for someone to say that Platinum has an even number, yet is roughly as rare as Gold.
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howaminotmyself
11 years ago
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Take a deep breath, slowly now. You don't want to hyperventilate.
Wait, do you mean to say we're all stardust?
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dappled
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Every single atom of your body was made inside a star (and most likely not the sun). We all come from the stars!
Can I start hyperventilating again now? Please? :D
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howaminotmyself
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Hehe, I kind of already knew that. Don't ask me how, just sounds logical to me. :P
But please, tell me more about the universe! What star feels like "home" to you?