Nothing happens
You Die
pain
you die
you die...
it doesn't.
You can get chemical burns along your throat and stomach if you swallow lye.
you turn orange
You burp bubbles
It depends on how much you swallow. If it is a large amount, you could get diarrhea and/or vomit.
You Swallow Or you slobber Or your mouth chokes You Swallow Or you slobber Or your mouth chokes
This too will pass.