00:01
Okay, so we're talking about the carbon, the decay of 14 -6 carbon.
00:08
And so we want to figure out, like, just to figure out, like, can we always be using carbon dating? maybe that's the sort of crux of the question.
00:18
And so to play with that question, we say, okay, well, let's say we have a mass of 72 grams.
00:24
How long until all of the 14 -6 carbon is gone? so first we have to consider that we have to figure out how many of these carbon 16s are available.
00:37
So let's find our initial n -not.
00:40
So if there's 72 grams, i looked up the natural abundance and it was one part per trillion.
00:47
The natural abundance of carbon 146, so one part per trillion, so that's one times 10 to the 12.
00:54
And carbon is 24 .305 grams per mole and 6 .022 times 10 to the 23 particles per mole.
01:18
And yeah, so let me write down what i got for that number.
01:29
1 .78 times 10 to the 12 particles.
01:45
And then now we want one to be left, so we just have to solve our usual n equals n -e to the minus lambda t...