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

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

The correct options are A and E.

In chemistry, there are two types of change, these are physical and chemical changes. A physical change is one in which no new substance is formed while a chemical change is one in which a new substance is formed. Looking at the options given above, it will be seen that the options given in B,C, and D did not produce any new material. But the options given in A and E bring about production of new materials, because oxidation process takes place in the two cases. Chemical change is indicated by the colour change in option A and rust is produced in option E.

A & E for sure but not sure about B for the reason that if you boil water until it is no longer in a liguid form the hydrogen and oxygen are no longer attached to the sodium. So maybe B too.

Hope this helps :)

answer: the primary difference between a hypothesis and a theory is that b hypothesis is falsifiable, but a theory has been proven to be correct. theory is an explanation of something that is happening but hypothesis is a guess of something that can happen

explanation: