Fixed place that you use to help you to find position or measurements ?

Achemist 16 drop copper metal from copper chloride solution. the chemist place is 0.50 g of aluminum foil in a solution containing 0.75 g of copper (ii) chloride. a single replacement reaction takes place. which statement explains the maximum amount of copper that the chemist can extract using this reaction?

The atomic number, or number, is the described as the number of in the nucleus of an chemical element.

How might this scientific phenomena be explained? a paper clip floats on water.