Mole Concepts

A mole is a unit that measures the amount of substance. It is defined as the number of atoms in exactly 12 grams of carbon-12, which equals 6.022 × 10²³ particles (Avogadro's number).

Avogadro's Number is 6.022 × 10²³ particles per mole, representing the number of atoms, molecules, or ions in one mole of a substance.

Molar mass is the mass of one mole of a substance (atoms, molecules, or ions) and is expressed in grams per mole (g/mol). It is numerically equal to the atomic or molecular mass.

Number of moles (n) = Mass (g) / Molar Mass (g/mol).

Number of particles = Moles × Avogadro's Number.

At STP, 1 mole of any ideal gas occupies 22.4 liters.

Moles = Concentration (mol/L) × Volume (L).

The coefficients in a balanced chemical equation represent the ratio of moles of reactants and products.

To determine the empirical formula, convert the mass of each element to moles, divide by the smallest number of moles, and use the ratios to find the simplest whole number formula.

Calculate the moles of each reactant, and compare the mole ratios to the balanced equation. The reactant with fewer moles than required by the ratio is the limiting reactant.