Make up the chemical formulas of compounds with chlorine (I) of the following elements

Make up the chemical formulas of compounds with chlorine (I) of the following elements (the chlorine symbol in these formulas is put in second place): a) aluminum b) calcium

Metals react with non-metals, while the non-metal atom takes as many electrons as it lacks until the outer level is completed, for example, the chlorine atom lacks one electron, since it is in group 7. And the metal gives up all the electrons of the outer level (their number is equal to the group number). Therefore, chlorine exhibits valence 1 in these compounds, and aluminum and calcium – 3 and 2, respectively.

Formulas of substances will look like this: AlCl3 – aluminum chloride, CaCl2 – calcium chloride.