How many atoms are in \(1.50 \mathrm{~mol}\) of carbon-12? How many grams does this much carbon-12 weigh?

Imagine having a single cookie and wanting to know how many crumbs it could make. Avogadro’s number works similarly for atoms. It’s a constant that gives us the number of particles, usually atoms or molecules, in one mole of substance. This astounding number is approximately 6.022 x 10^23.
For our carbon-12 example, multiplying 1.50 moles by Avogadro's number gives us the total count of atoms. Just like knowing the crumb count tells us how many will scatter if the cookie crumbles, Avogadro's number lets us quantify the incredibly vast number of atoms in a substance with relative ease.

Consider a classroom filled with different sets of building blocks. Molar mass can be equated to knowing the total weight of one set of blocks. It's the weight of one mole of a substance, usually expressed in grams per mole (g/mol).
For carbon-12, which is used as a standard, its molar mass is exactly 12 g/mol. So, if you have 1.50 moles of carbon-12, a simple multiplication operation gives you the mass in grams, much like estimating the collective weight of block sets in your classroom based on the weight of one.

In cooking, recipes tell us the amount of each ingredient needed for a dish. Stoichiometry is the 'recipe' of chemistry. It's a section of chemistry that deals with the relative quantities of reactants and products in chemical reactions.
In our example, stoichiometry assists in understanding how 1.50 moles of carbon-12 relate to other reactants or products in a reaction, like portions of ingredients translating to parts of a meal. Through stoichiometric calculations, chemists can precisely tweak amounts to obtain desired products, avoid waste, and maximize efficiency in reactions.

If we liken atoms to tiny fruits in a market, each having different sizes and masses, atomic mass units (amu) would be the scale that helps compare their weights. It is a standard unit of mass that quantifies how heavy an atom is, relative to one twelfth of a carbon-12 atom.
This unit gives us a way to discuss the incredibly minimal mass of atoms in terms we can comprehend. When talking about carbon-12, it has an atomic mass of exactly 12 amu, meaning it's used as a reference point for defining the atomic mass unit itself. Knowing the amu allows chemists and physicists to discuss and compare different atoms on a microscopic scale, facilitating deeper understanding and precise communication in the field of chemistry.