Not counting hydrogen, why is it that elects in column 1 of the periodic table do not tend to react with each other?

It tends to be very difficult to react because they all have 1 electron and want to have a full valence state. To achieve this full state, they follow the octet rule and give away their electron almost every single time. Since they would need 7 more electrons to be full via accepting electrons, they prefer to give them away. Hydrogen does not act like this because it doesn't follow the octet rule and only needs 2 electrons to be full.

Yes it would be a physical change.

The water cycle increase the water content in the earth atmosphere