How do scientists know that the layer of ice they are looking at was deposited in
1883? (CK-12)

Use examples from the article to explain one positive and one negative effect that chemistry has had on society.

Ican determine the molar mass of an element by looking on the under the atomic mass for the element. for example the molar mass of phosphorus is 30.974 grams/mole. avogadro’s number tells me the amount of representative particles in 1 mole of any substance. this means 12.011 gram sample of carbon and a 32.0 gram sample of sulfur have the same number of atoms.

The fact that the total amount of energy in a system remains constant is a(n)