Aww man, I love these types of problems!!!
So, it's a simple formula:
P1*V1/T1=P2*V2/T2
In this case, we remove V(volume) as there is none listed, leaving this:
P1/T1=P2=T2
Think you got it from here? All you gotta do is plug in the numbers and solve
If you have any further problems, just let me know!!
Number of atoms : 1.26 x 10²³
<h3>Further explanation </h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
0.21 moles of Al, so n = 0.21
Number of atoms :

It's A, metals. Metals are solid at room temperature but still very malleable and the best conductors. Metalloids can still conduct electricity but nowhere near as well as metals.