Question

when you were building a dune buggy but given only the mass of the components present, you had to convert to the number of each component you had. for a chemical reaction, you may also be given mass instead of number of moles.
what quantity would you use to convert mass to number of moles for use in calculations?
moles
mass
atomic number
molar mass
number of molecules/particles

Explanation:

The formula to convert mass ($m$) to moles ($n$) is $n=\frac{m}{M}$, where $M$ is the molar mass. Molar mass is the mass per mole of a substance. Moles and mass are the quantities being related (so they can't be the conversion factor). Atomic number is related to the number of protons in an atom and not used in this mass - to - moles conversion. Number of molecules/particles is related to moles via Avogadro's number ($N = n\times N_A$) but not directly to mass.

Answer:

Molar mass