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Title: Sciencey question. Post by: RED-DOG on November 05, 2017, 11:31:43 AM If my facts are wrong please correct me.
Radium is mined. Radium has a half-life of 1600 years. How come it hasn't used up all it's radioactivity already? Title: Re: Sciencey question. Post by: tikay on November 05, 2017, 11:54:54 AM If my facts are wrong please correct me. Radium is mined. Radium has a half-life of 1600 years. How come it hasn't used up all it's radioactivity already? I'm not 100% sure, but I think radium is created by the decay of uranium atoms. If so, radium is being "made" all the time, as uranium atoms decay due to their own half life. I don't think radium is "mined" as such, and it only gets excited when exposed to the environment. I assume it is inert in its natural state. Title: Re: Sciencey question. Post by: RED-DOG on November 05, 2017, 12:01:22 PM Ah, so radium isn't found as radium, it's a by product?
Title: Re: Sciencey question. Post by: tikay on November 05, 2017, 12:20:21 PM Ah, so radium isn't found as radium, it's a by product? That's my (vague) understanding, yes. You mine other stuff, and a tiddly-widdly bit of radium comes with it as a freeroll. Title: Re: Sciencey question. Post by: Jon MW on November 05, 2017, 12:24:52 PM If my facts are wrong please correct me. Radium is mined. Radium has a half-life of 1600 years. How come it hasn't used up all it's radioactivity already? It's a half life - the radioactivity halves in 1600 years and it starts off at a very high number - so it will take a long time to disappear. Like Tikay said it can be formed from the decay of uranium; but it isn't strictly a by product - it is the uranium atom just without some of it's protons and neutrons which were lost through the radioactive decay of the uranium. Uranium has a half life is up to 4.5 billion years so a very long time for either it or the radium to run out.* *all credits to scientist wife for all the science :) Title: Re: Sciencey question. Post by: tikay on November 05, 2017, 12:28:00 PM That's the other point - something with a half-life NEVER (quite) disappears, or that is my understanding. Socks and car keys, of course, don't have a half life.
Title: Re: Sciencey question. Post by: RED-DOG on November 05, 2017, 12:34:06 PM That's the other point - something with a half-life NEVER (quite) disappears, or that is my understanding. Socks and car keys, of course, don't have a half life. I once hypothesised that if you started in Leeds and drove towards London at 1000 miles an hour but stopped halfway for 1 second before driving half the remaining distance then stopping for 5 seconds and so on, you would never actually get to London. Title: Re: Sciencey question. Post by: RED-DOG on November 05, 2017, 12:37:53 PM If my facts are wrong please correct me. Radium is mined. Radium has a half-life of 1600 years. How come it hasn't used up all it's radioactivity already? It's a half life - the radioactivity halves in 1600 years and it starts off at a very high number - so it will take a long time to disappear. Like Tikay said it can be formed from the decay of uranium; but it isn't strictly a by product - it is the uranium atom just without some of it's protons and neutrons which were lost through the radioactive decay of the uranium. Uranium has a half life is up to 4.5 billion years so a very long time for either it or the radium to run out.* *all credits to scientist wife for all the science :) 4.5 billion years? Shut the front door! Title: Re: Sciencey question. Post by: RED-DOG on November 05, 2017, 12:40:11 PM BTW- Is it just me or is the notion of a scientific wife sexy?
No lawsuits please, no offence intended, other types of wife are available. Title: Re: Sciencey question. Post by: Jon MW on November 05, 2017, 12:48:49 PM If my facts are wrong please correct me. Radium is mined. Radium has a half-life of 1600 years. How come it hasn't used up all it's radioactivity already? It's a half life - the radioactivity halves in 1600 years and it starts off at a very high number - so it will take a long time to disappear. Like Tikay said it can be formed from the decay of uranium; but it isn't strictly a by product - it is the uranium atom just without some of it's protons and neutrons which were lost through the radioactive decay of the uranium. Uranium has a half life is up to 4.5 billion years so a very long time for either it or the radium to run out.* *all credits to scientist wife for all the science :) 4.5 billion years? Shut the front door! There are different types of uranium with different half lives. I had a look on wikipedia and particularly like this line, "Uranium-238 is the most stable isotope of uranium, with a half-life of about 4.468×109 years, roughly the age of the Earth" - love the roughly the age of the Earth tacked on to the end :D BTW- Is it just me or is the notion of a scientific wife sexy? No lawsuits please, no offence intended, other types of wife are available. :)up Title: Re: Sciencey question. Post by: AndrewT on November 05, 2017, 01:32:34 PM That's the other point - something with a half-life NEVER (quite) disappears, or that is my understanding. Socks and car keys, of course, don't have a half life. I once hypothesised that if you started in Leeds and drove towards London at 1000 miles an hour but stopped halfway for 1 second before driving half the remaining distance then stopping for 5 seconds and so on, you would never actually get to London. This is a version of one of Zeno's paradoxes. https://en.m.wikipedia.org/wiki/Zeno's_paradoxes Title: Re: Sciencey question. Post by: RED-DOG on November 05, 2017, 01:59:02 PM That's the other point - something with a half-life NEVER (quite) disappears, or that is my understanding. Socks and car keys, of course, don't have a half life. I once hypothesised that if you started in Leeds and drove towards London at 1000 miles an hour but stopped halfway for 1 second before driving half the remaining distance then stopping for 5 seconds and so on, you would never actually get to London. This is a version of one of Zeno's paradoxes. https://en.m.wikipedia.org/wiki/Zeno's_paradoxes I think you'll find he copied me. |