Q. Which law states that equal volumes of gases, at the same temperature and pressure, contain equal numbers of molecules?
✅ Correct Answer: (B)
Avogadro's law
Explanation: Avogadro's law states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules (or moles). Dalton's law concerns partial pressures. Boyle's law relates pressure and volume at constant temperature. Gay-Lussac's law relates pressure and temperature at constant volume (or in another form, volume and temperature at constant pressure depending on naming), but none of these describe equal numbers of molecules in equal volumes — that's Avogadro.
Explanation by: Sikhar Chaudhary
Avogadro's law states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules (or moles). Dalton's law concerns partial pressures. Boyle's law relates pressure and volume at constant temperature. Gay-Lussac's law relates pressure and temperature at constant volume (or in another form, volume and temperature at constant pressure depending on naming), but none of these describe equal numbers of molecules in equal volumes — that's Avogadro.