Answer:
2.1 x 10^24 Cr ions
Explanation:
You need to multiply the 3.5 mol by the Avogrado's number (6.022 x 10^23) to get your answer.
Answer: A. Pollutants
Explanation:
"A pollutant is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. ..." - Wikipedia