radial nodes

what is a radial node? why does a 3p orbital have it and 2p does not?

"Why" is a meaningless question, in all probability.

No not really.... Just requires a relatively high level of knowledge in quantum mechanics!

You misunderstand.

The question of "why radial nodes exist" is meaningless, much as questioning the postulates of quantum mechanics, or the fact of the conservation of energy, is meaningless.

The nodes fall out of the equations... Yes you assume postulates but radial nodes aren't a postulate of QM

I know that.

That doesn't mean they have a "why". They simply are a statement of the fact of their existence.

Much like Feynman says of partial reflection- "Nobody knows why nature nature acts like this, she simply does. Probably the question has no meaning".

Well is this not the case with anything we ask the question why to then? Just because this lies close to fundamental postulates doesn't mean we can't ask why it comes about.

Yes, that is the case.

I don't consider your answer to explain "why it comes about".
It really, I think, depends on how one decides to interpret the question.
They do not exist because of quantum mechanics. They just exist, and quantum mechanics describes the fact if their existence. They are a feature of reality described by quantum theory.

I don't understand why it's such a big deal to you, nor why you seek to "take me to task", or whatever it was that started you off on this conversation.