Calculating Current from AL3 Atomic Mass

[ctech4285]

ok i was thinking
AL3 atomic mass of 13, has 4.6e23 atom per kg
and 13.8e23 charge per kg
multiply that by 1.6e-19 and we have 2.2e5 coulomb
so moving this 1kg of AL3 past a point ones per second would equal a current of 22KA

 

[NobodySpecial]

Al has an atomic number of 13 which means that 13g of it has 6x10^23 atoms.
So a kilo has rather more atoms - about 1000/13 moles = 4.60x10^25 atoms

Getting all of them to Al 3+ would be tricky, but if you could then, yes you would have quite a lot of current flowing.

 

[ctech4285]

ok 2.2e7 C per kg
so 2.2MA
i am wondering what would happen if you shoot a few grams out of a rifle at >300m/s

is there something i can buy that has + or- charge, like hosehold related?

 

[K^2]

That's 4.6e25 atoms and 2.2e7 coulombs. Assuming you want this thing to be spherical, you are proposing stuffing these 2.2e7 coulombs into a sphere 8.9cm across. That means density of 5.94e10 coulombs/meter. I'm getting total energy of 2.5e14J. That's about 60kT. A small nuke worth of energy stored purely in electrostatic repulsion of Al3+ ions. Good luck containing that.

(Edit: Just for fun, you can also try computing electric field from it, and estimating the closest distance a living being can stand to this sphere without getting its electrons ripped out.)

 

[ctech4285]

oops i didnt think of that..hmm...
whats the limit on charge density for normo self containing stuff?

 

[NobodySpecial]

You could do it as a stream of ions in a vacuum, you would need one heck if a filamant to emit 1kg/s of Al3+ though!

 

[K^2]

No, you couldn't. You need a confinement of some sort. Your only option is magnetic confinement, and then you end up energies with many magnitudes greater, and absolutely no materials that could actually sustain the fields.

Edit: The unbalanced charges you can actually store in normal materials are VERY small.

 

[NobodySpecial]

No, you couldn't. You need a confinement of some sort. Your only option is magnetic confinement, and then you end up energies with many mag

The OP only said they wanted to move a Kg of Al ions/second - they didn't say anything about doing it in one lump.
You would need a fairly chunky inductor for the ICP at one end and really-really-good grounging on the target at the other end!

Admittedly the current in a really big ion source is normally only a few 10mA - but that's just an engineering detail.

 

[Redbelly98]

Al has an atomic number of 13 which means that 13g of it has 6x10^23 atoms.

Umm, no, that is not what the atomic number means. It means that aluminum atoms have 13 protons. But they also have 14 neutrons (usually) which contribute significantly to the overall mass. Aluminum's atomic mass is 26.98 g/mole.

 

[K^2]

The OP only said they wanted to move a Kg of Al ions/second - they didn't say anything about doing it in one lump.

Ah, I see. Yes, a high velocity beam with low density should be possible.

 

[NobodySpecial]

Umm, no, that is not what the atomic number means. It means that aluminum atoms have 13 protons. But they also have 14 neutrons (usually) which contribute significantly to the overall mass. Aluminum's atomic mass is 26.98 g/mole.

ooops - sorry, lack of coffee.

 

[ctech4285]

how does PH relate to the static charge of an substance?

hey two charged objects moving on parallel paths wouth have an atractive magnetic force and a repuslive static force, is that right?

 

[Redbelly98]

how does PH relate to the static charge of an substance?

It doesn't.

hey two charged objects moving on parallel paths wouth have an atractive magnetic force and a repuslive static force, is that right?

Yes, if they are both positive or both negative charges.

 

[K^2]

And the attractive magnetic force can never exceed the repulsive force.