Why are the numbers in an element’s atomic mass the same as the numbers in its molar mass ignoring the units?

Question

Why are the numbers in an element’s atomic mass the same as the numbers in its molar mass ignoring the units?

In: 3

Answer 1

This is just definitional, isn’t it?

This is like asking “why does ten thousand 1-gram weights weigh 10 kilograms?” Molar mass is the mass of 1 mol (a quantity) of an element, and the atomic mass is that divided by the quantity. Replace the word “mol” with “million” (it’s not 1 million, but it helps you see the tautology).

Rewritten this way the question asks: “why does an atom have the same mass as 1 millionth of a million atoms?”

The atomic mass is *defined* as “the molar mass, divided by the number of atoms in a mol”