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which laboratory activities involve chemical changes? check all that apply.

leaving a copper penny in vinegar until it turns green
boiling saltwater for several minutes until only solid salt remains
extracting iron filings from a sand mixture using a magnet
crushing a rock with a hammer to extract mineral deposits
putting an iron nail outside for a month and observing changes

The correct activities are leaving a copper penny in vinegar until it turns green, and putting an iron nail outside for a month and observing changes.

Explanation:

The formation of the green component on the copper penny and the formation of rust on the iron nail when kept outside for a month are the illustrations of chemical changes. On the other hand, extracting fillings or iron from a sand mixture with a magnet, boiling salt water away, and crushing rock with a hammer are the illustrations of physical modifications.

false

because it does not have the potential to be entirely used up

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >