I'm pretty sure it's B because carbon atoms are in all living organisms. They can also be bonded in different varations.
Answer:The green growing on the penny of copper and the rust forming on the nail of iron are chemical changes. Boiling away salt water, scraping iron filings from a mixture of sand with a magnet, and breaking a rock with a hammer, are physical changes.
Explanation:
Answer:
b. Its concentration is half that of the chloride ion
Explanation:
As the calcium chloride formula is CaCl2
CaCl2 <--> Ca + 2 Cl-