Sciencey question.

[RED-DOG]

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?

[tikay]

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.
 

[RED-DOG]

Ah, so radium isn't found as radium, it's a by product?

[tikay]

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.

[Jon MW]

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

[tikay]

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.

[RED-DOG]

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.

[RED-DOG]

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!

[RED-DOG]

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.

[Jon MW]

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

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.

 

[AndrewT]

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

[RED-DOG]

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.