RTP stands for Room Temperature and Pressure.
One mole of any gas has a volume of 24 dm 3 or 24,000 cm 3 at rtp (room temperature and pressure). This volume is called the molar volume of a gas. This equation shows how the volume of gas in dm 3 at rtp is related to the number of moles: volume of gas at rtp = number of moles × 24.
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