# For a given substance, what information links mass to moles? number of particles to moles?

One mole of substance specifies $6.022 \times {10}^{23}$ particles.
Thus $1 \cdot m o l$ of say, $C {O}_{2} \left(g\right)$, represents $6.022 \times {10}^{23}$ carbon atoms, and $2 \times 6.022 \times {10}^{23}$ oxygen atoms. Since I know from the Periodic Table, that $6.022 \times {10}^{23}$ carbon atoms have a mass of $12 \cdot g$, and that $6.022 \times {10}^{23}$ oxygen atoms have a mass of $16 \cdot g$, it follows that 1 mole of $C {O}_{2}$ has a mass of $44 \cdot g$. Do you follow this?