Why the bromine and air can mix together? A. Bromine is denser than air
B. Bromine is lighter than air
C. Bromine molecules moved upwards and molecules in air moved downwards
D. Molecules in bromine and air moved randomly
Chooses the correct statement from the above

D. Molecules in bromine and air moved randomly  

Explanation:

The molecules of both bromine and air are in the gas phase.

Since the molecules of gases are far apart and moving randomly, the bromine and air molecules can easily mix together.

A is partially correct. bromine is denser than air, but that doesn't explain why they mix.

B is wrong. Bromine is denser than air.

C is partially correct. The molecules of bromine and air moved upwards and downwards, but the also moved randomly in many other directions.