What does below chemistry rebus means?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

Keyboard words are not in alphabetical order, Why?

Can you move 2 matchsticks to form four equal sized squares.

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

There is a number which when you multiply by 3 and subtract 2 from the result, then the resulting number is the reverse of the actual number.

What is the smallest number that stands true on the statement?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

I am a ten letters word
The first four letters have the power to rule,
Next, four-letter can be eaten.
The next three-letter represents a lady.
I can fly as well

what am I looking for?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?