To fulfill the octet rule, electron sharing leads to how many electrons around each atom? 4 5 7 8

Put these processes of the water cycle in the correct order, starting at the point where the water is in the lake: 1. water evaporates into the atmosphere 2. rain, snow, or other precipitation falls 3. water collects into larger bodies of water 4. water vapor condenses into liquid water

Which of these conditions most likely produces an unstable isotope?

How would the number of moles (n) of o2 change if the atmospheric pressure doubled but all other variables stayed the same