What Am I Riddles

Question: I'm heavy but not backwards.

What am I?

Question: I have all of your knowledge but could fit in your hands.

What am I?

Question: I am the only organ that named myself.What am I?

Question: 100 feet in the air, yet its back is on the ground.

What is it?

Question: I'm red, blue, purple and green.
No one can reach me, not even the queen.

What am I?