Planets reflect sunlight. Most planets are close enough to the sun that they can reflect its light and that is why you can see them. Some planets that are far from the sun do not light up because they have no light to reflect.
I hope this was a satisfying answer. Have a great night!
B - Atomic number. Dmitri Mendeleev organised the table according to atomic weight, however this caused problems with elements such as iodine and tellurium, Iodine has a higher mass, but a lower atomic number. And to make iodine in the same group as similar elements (halogens), Mendeleev had to break his own rules and put it before tellurium in the table. Moseley fixed this problem by ordering the elements according to atomic (proton) number.
Answer:
Oxidation state shows the total number of electrons which have been removed from an element (a positive oxidation state) or added to an element (a negative oxidation state) to get to its present state
It is going through a physical change