How many moles is
55 g of Naci?
0.025 g of NaCO3?

How has the scientific community addressed the safety of chemicals? a. chemicals are repeatedly tested, even those that have existed for a long time. b. existing chemicals are tested if they have never been tested before. c. chemicals are tested if they are suspected to have caused a problem. d. only new chemicals are tested.

What does a numerical subscript following an element in a chemical formula mean?

Which of the following isotopes has the same number of neutrons as phosphorus-31?