What does below chemistry rebus means?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

During which month do people sleep the least?

What can go through glass without breaking it?

A person was found dead on a big green land with no trees or buildings around. When the police arrived, they found a piece of rock lying next to him and the man was wearing clothes comprising of red, blue and yellow colours.

Can you tell who the person is and what was the cause of death?

If you paint a brown house white it will become a white house. If the stoplight changes from red to green, then the light is green. So, if you throw a white shirt into the Red Sea, what will it become?

I am never scared but became petrified and can’t live in a house but would die to make one. What am I?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?