k is the constant of proportionality

and t is time

Do you understand?

Yeah

Okay

We know that argon has 8 electrons, and thus has little to no reactivity

Do you agree

Yeah

Okay

We know that by using quantum physics, we can calculate the half life of potassium 40, an isotope of potassium, to be 1.25 billion years

Do you agree?

I did not know that

Are you going to continue?

Yes

Okay

We know that K-40, potassium 40, decays into two atoms

since it’s radioactive

Argon 40, and Calcium 39

We know that 11% is argon 40, and 89% is Ca 39

Isn't it Ca-40?

@NickC64 sorry I had to go, I'm at work)

No

Lol

One of the neutrons turns into an electron

Pretty sure

Maybe proton

Alright

And if we have some sort of volcanic eruption, the lava is illiquid

Liquid**

That means that any argon 40 in there, since it’s low reactivity, is free to move out of the lava

Perhaps an error in the wikipedia article then, it says Ca-40

It’s probably an error

@PhumoZTYPE anyway

Because of this, we know that any argon 40 in the rock must have came from the parent element

Which is K-40

Yup

Good

Now, we can get to the fun part

It would be easier if I could send pictures

Yeah I guess

We can take our original equation, N_0 times e^-kt = N(t)