What does below chemistry rebus means?

Can you decipher the two rows to find the hidden word?

There was a minor accident with a doctor's son but the doctor noticed no major injury. After the treatment, the father of that doctors son is sitting with the son of the doctor without the doctor being in the room.

How can this be possible?

A mathematician couple was having a Frappuccino in Starbucks sitting opposite to each other. Suddenly the guy noticed the text written on the paper in front of them and exclaimed that it was wrong. The girl denied it and said it is appropriate. Both are correct. What is written on the paper?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

Which is faster, Heat or Cold ? Explain.

Decode below rebus
D
N
A
T
S , D

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

The Little ant seems to be always confused. Do you know why?

Suppose we lay down two cups in front of you. One of the cups is filled with tea and the other one with coffee. Now we ask you to take a spoonful of tea and mix it with the coffee. At this moment, the coffee cup has a mixture of tea and coffee. You have to take that mixture (spoonful) and add it back to the tea.

Can you now tell if the cup of coffee has more tea or the cup of tea has more coffee?