13 atoms are in the chemical formula AI(PO4)3
hope that helps :-)
Explanation:
Atoms are the smallest unit of matter that can't be broken down chemically. Molecules are groups of two or more atoms that are chemically bonded. Ions are atoms or molecules that have gained or lost one or more of their valence electrons and therefore have a net positive or negative charge.
Density is a physical property. It's measured and doesn't change the object chemically.
Low electron affinity and large atomic radius
Metallic character decreases across a period (from left to right) and increases down a group.
Electron affinity increases from left to right within a period. This is caused by the decrease in atomic radius. Electron affinity decreases from top to bottom within a group. This is caused by the increase in atomic radius.
