Answer:
Measuring its density and comparing your result to a list of known densities, or other properties that give you useful info
Explanation:
You can use observations about substances to form a hypothesis about the substance by comparing it to others. Ex: if something is magnetic it must be made of one or more of the elements iron, cobalt, or nickel.
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.
