Answer:
Five Laboratory Safety Rules:
1). Do not eat in the laboratory.
2). Do not touch any chemical or reagent unless you are told to do so.
3). Neither play in lab, nor sit on the table.
4). Don't remove labels on any reagent.
5). Don't taste anything in the laboratory, no matter how familiar it appears.
Hope it helps.
Ion is an atom or molecule with a net electric charge due to loss or gain of one or more electrons.
B. Theory
The hypothesis that stand the test of time (often tested and never rejected) is called theory. A theory is supported by a great dealcof evidence.