Which theory or law describes the orientation of contact and the amount of energy needed for atoms to undergo chemical reactions?

Can you guys me with question no. 5!

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.

How do i turn 2 s into one in the products