What does below chemistry rebus means?

Which English verb becomes past tense just by rearranging the letters?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

A lion and its tamer are standing inside a cage that measures 1 unit in radius. Both of them can effortlessly run at the speed of 1 unit maximum.

1) Suppose the lion is hungry, will he be able to eat up the tamer?
2) If yes, how long can the tamer survive?

As shown in the image, the nine Dogs are square fenced. By constructing just two square fences can you make sure that two Dogs cannot meet each other without crossing the fence?

Two batsman each on 94 runs. Seven runs needed to win in last 3 balls. Both make 100*. How?

Can you count the number of squares in the given picture?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

There are forty elephants and they have forty-fore heads. How can this be possible?