Safety boundary
Use paper models, supplied data, and approved simulations only. No unsupervised reactive mixtures are required.
Explicit chemistry instruction
A mole is a counting unit equal to 6.022×10²³ entities. The entity may be atoms, molecules, ions, formula units, or other specified particles.
The mole bridges microscopic particle counts and macroscopic measurements. Always name the entity being counted.
Scientific notation and dimensional analysis prevent scale errors when converting between particles and moles.
Vocabulary: mole; Avogadro constant; entity; particle count; dimensional analysis.
Worked example
2.00 mol of molecules contains 2.00×6.022×10²³ = 1.20×10²⁴ molecules.
Guided question
How many molecules are in 0.250 mol? Show the conversion factor.
Independent work
- Convert four mole amounts to particle counts.
- Convert two particle counts back to moles.
- Label the entity in every answer.
Misconception check
A mole is not a mass unit; it is a counting unit.
Formative check
What quantity connects moles and particle number?
Reveal response
Avogadro's constant, 6.022×10²³ entities/mol.
Mentor evidence conference
Ask Archaemenes to audit units, conversion factors, equation coefficients, and model assumptions.
Teacher guidance
Foundation: Use one-step conversion frames.
Core: Perform mole↔particle conversions with units.
Extended: Analyze significant figures and entity choice.