My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

I am a type of word that is spelt incorrectly or used differently, on purpose for humour. What am I?
Hint 1: You can find me in a joke.
Hint 2: I am a play on words.

Why do people go to bed?

I am five letter word that is under you.
If you remove my 1st letter, then I am over you.
If you remove my 1st and 2nd letters then I am all around you.

Who am I?

I cannot talk, but I always reply when spoken to. What am I?

Which is the rope you never skip with?

Through your logical capabilities, can you make 7 an even?

I know a country, If you remove the last alphabet of its name, it will become a part of your body. Do you name it?

What does below rebus means ?

What has a bottom at the top?