Mole

Definition

A mole is a unit of measurement in chemistry that represents $6.022 \times 10^{23}$ particles (atoms, molecules, etc.). It is fundamental for quantifying the amount of substance in thermodynamics and gas laws.

5 Must Know Facts For Your Next Test

1. Moles help relate macroscopic quantities of substances to microscopic particles.
2. The Avogadro constant ($6.022 \times 10^{23}$) defines the number of particles in one mole.
3. In ideal gas law calculations, moles are used to quantify the amount of gas present.
4. The molar mass of a substance (in grams per mole) connects mass to moles.
5. Moles play a crucial role in determining the number of collisions and energy exchange between gas molecules.

Review Questions

• What is the Avogadro constant and how does it relate to a mole?
• How do you convert between grams and moles using molar mass?
• In the context of ideal gases, why is it important to know the number of moles?

Related terms

Avogadro's Number: The number $6.022 \times 10^{23}$ representing the quantity of atoms or molecules in one mole.

Ideal Gas Law: An equation of state for an ideal gas: $PV = nRT$, where $P$ is pressure, $V$ is volume, $n$ is number of moles, $R$ is the universal gas constant, and $T$ is temperature.

Molar Mass:

The mass (in grams) of one mole of a given substance.