Answer:
The more you add the less it weighs. What is it?
I am used when you jump off a bridge for fun.
It's red liquid but not liquid and it's not red. What is it?
Whoever makes it, tells it not. Whoever takes it, knows it not. Whoever knows it, wants it not. What am I?
If I drink I die. If I eat I am fine. What am I?
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.