N2-3H2 → 2NH3 How many moles of hydrogen, H2, are needed
to react with 2.0 moles of nitrogen, N2?

If many scientists conduct the same or similar experiments, and all obtain similar results, a can be written, which is a generally agreed-upon statement that explains and predicts how a natural phenomenon works.

How many atoms or molecules are there in a mole of a substance?

What is the scientific name for weight?