Answer:
A
Explanation:
Because it does not change entirely.
Atomic radius is determined as the distance between the nuclei of two identical atoms bonded together. The atomic radius of atoms generally decreases from left to right across a period.
Answer:
Two molecules of hydrogen combine with two molecules of oxygen to form hydrogen peroxide. Hence, its chemical formula is H2O2. It is the simplest peroxide (since it is a compound with an oxygen-oxygen single bond). Hydrogen peroxide has basic uses as an oxidizer, bleaching agent and antiseptic