Is this compound aromatic? Actually, no, it's not. In fact, it's antiaromatic. Let's go ahead and find out why.
- Is it cyclic? Yes.
- Is it fully conjugated? Yes, it is. Positive charges can participate in resonance, so the entire every single atom can resonate.
- Is it planar? Yep.
- Does it have 4+2 number of pi electrons? No, it actually has 2,4. It only has 4 pi electrons which, if you recall, is one of the really bad numbers. This is a 4n number, so it's got 4n number of pi electrons. That means this is going to be antiaromatic. Not so bad, right?
Let's move on to the next question.