We have discussed how scientists use chemical reactions for important things, such as making our drinking water safe. Explain a
chemical reaction you experience in your daily life.
What is a chemical reaction? What is a chemical reaction you witness
often? How do you know this is a chemical reaction? What signs
prove this is a chemical reaction.
Response: A chemical reaction I witness before is rust example
verdigris on copper and tarnishing of silver.

a:

by the combination of an unlimited number of elements

with this one i know the answer in craters one reason i looked it up and i learned about it there is my evidence

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.

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