Proton:
Positively charged
Inside nucleus
Mass - 1
Electrons:
Negatively charged
Outside the nucleus
Mass - 1/2000
These gases all have similar properties under standard conditions: they are all odorless, colorless, monatomic gases with very low chemical reactivity. The six noble gases that occur naturally are helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn).
