What does below chemistry rebus means?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

What you cannot hold but it is yours?

What has hands, but can’t clap?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

There are three boxes. One is labeled "APPLES" another is labeled "ORANGES". The last one is labeled "APPLES AND ORANGES". You know that each is labeled incorrectly. You may ask me to pick one fruit from one box which you choose.

How can you label the boxes correctly?

Can you count the number of rectangles on a chessboard?

John Went to the nearby store in a Mall to buy something for her home. Below is the conversation between the two:

John: How much for the one?
Shopkeeper: It is $2
John: How much for the Eleven?
Shopkeeper: It is $4
John: How much for the Hundred?
Shopkeeper: It is $6.

What is John buying?

Those who excel at picture puzzles to find hidden objects often possess keen attention to detail, high IQ, and the ability to process visual information at lightning speed.