Question

Number of Ni atoms in 3.4moles of Ni?

Answer 1

Do you know how many Ni atoms are in 1 mole of Ni? This would be the same as the number of things in 1 mole of anything.

Answer 2

Do you mean grams?

Answer 3

The [The problem doesn't say I would assume 6.022*10^23

Answer 4

1 mole of something will always be 6.022*10^23 somethings. That's just a standard set up for all mole measurements.
It is kind of like speaking of dozens. 1 dozen of something is always 12 somethings. Or 3 dozens of something is 3*12 = 36 somethings.
So, 1 mole of Ni is 6.022*10^23 Ni atoms. And 3 moles of Ni is 3*6.022*10^23 Ni atoms.

Does that comparison make some sense?

Answer 5

Yes, it does thank you!

Answer 6

Glad to help!
That was the way I was introduced into moles, and I think it sets up a great intuition for what a mole really is, since it seems so obscure when you start learning about them. :)

The more mathematical process is by unit conversions: x moles * (6.022*10^23 atoms / mole) = x*6.022*10^23 atoms. It's the same result as in the analogy above, but now we involved the units so you can see the conversion factor and unit cancellation. I find unit conversions great later on when you use molar mass (g/mol) to convert between grams and moles!