Some preventive steps, including bathing after exposure, may reduce symptoms. Chlorine is an element added to pools and hot tubs to help disinfect water, making it safer to swim in. It’s also ...

If you know the proton ... symbol for an element shows its nucleon number (A) at the top, and its proton number (Z) at the bottom. This symbol tells you that the chlorine atom has 17 protons.

Accompanying Lesson Plan: Lesson 3.2: Finding Volume—The Water Displacement Method The chart shows that atomic size and mass for the first 20 elements in the periodic ... hydrogen, and chlorine atoms.