Hey there! Hello!
When I was doing this part of chemistry, I found it easiest to do these problems with a chart. I've attached a picture of one that I printed out with some writing on it; I really wish I could find the actual picture I printed out, but I have so much on my computer and I know you need help ASAP.
So, first thing to keep in mind is what n and l mean. "n" is the principal quantum number/level, which basically means it's the top energy level. Then, one down from that is "l," which is the angular quantum number, or the sublevel. You can refer to these however you like. Keep in mind how the number that "l" is translates to the different letters that represent sublevels:
0=s sublevel, 1=p sublevel, 2=d sublevel, and 3=f sublevel.
<span>What the problem is asking you to do is define the subshell that has an "n" of 2 and an "l" of 1. Given what I've previously stated, the proper representation will be "2p," since your "l" value is equal to 2, or p.
I hope that my answer (and attachment) help you out! Feel free to ask me any additional questions if you have any. :-)</span>
