Sawing a board in half is a physical change not a chemical change the board doesnt change wood or whatever material it is is still would still be wood
If it were burned it would be a chemical change but its properties stay the same atomically so thats why its not a chemical change.
Yeah of-course!! It's valency by group most of the chemical property like electronegativity, ionization energy etc. by the combination of groups and periods...
Because it throws the earth off balance and if it does it often enough then it will soon add up.
The answer is motion, this is what I would go with because when you are dealing with gases it puts motion in the term of particles.
Answer: Fluorine and chlorine are gases. Bromine is one of only two liquid elements, and iodine is a solid.