* Rubidium (Rb) is an alkali metal in group 1 of the periodic table. It has a +1 charge when it forms an ion (Rb⁺).
* Chlorine (Cl) is a halogen in group 17 of the periodic table. It has a -1 charge when it forms an ion (Cl⁻).
To form a neutral compound, one rubidium ion (Rb⁺) combines with one chloride ion (Cl⁻), resulting in the formula RbCl. This compound is called rubidium chloride.
