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Avogadro's Law — FRCA Primary MCQ

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EasyPhysics & Clinical MeasurementAvogadro's LawFRCA Primary

Which gas law states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules?

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Correct answer: C — Avogadro's law

Avogadro's law states that equal volumes of ideal gases at the same temperature and pressure contain equal numbers of molecules. One mole of any ideal gas at STP (0°C / 101.3 kPa) occupies 22.4 L and contains 6.022 × 10²³ molecules (Avogadro's number). This is fundamental to understanding gas volumes and concentrations.

Reference: Al-Shaikh Stacey 2019 Essentials of Anaesthetic Equipment