instruction:
Given a scientific question, generate a correct answer to it.
question:
The direction of prevailing winds determines the type of what that usually moves over an area?
answer:
air mass

question:
Adding the number of protons plus the number of neutrons in an atom, decides it's approximate mass, what is another word for this value?
answer:
atomic number

question:
Covalent bond energies can be used to estimate the enthalpy changes of what?
answer:
chemical reactions