Chamber s contains 40% helium and chamber b contains 20% helium chambers are connected by a tube the molecules are free to cross which of the following will occur?

To determine what will happen when chambers A and B are connected and contain different concentrations of helium, we need to consider the principles of diffusion.

In this case:
- Chamber A contains 40% helium.
- Chamber B contains 20% helium.

Molecules tend to move from areas of higher concentration to areas of lower concentration, a process known as diffusion. Therefore:

- Since Chamber A has a higher concentration of helium (40%) compared to Chamber B (20%), helium molecules will naturally move from Chamber A to Chamber B until the concentrations begin to equalize.

Given the options provided, the correct outcome is:

**A. Some helium will move from chamber A to chamber B.**

So, the correct answer is A.