Density of Cl₂ (Chlorine) at STP
Chlorine gas (Cl₂, molar mass 70.9 g/mol) has a density of approximately 3.17 g/L at STP, much heavier than air.
How to use this tool
- Enter molar mass in the fields above.
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- Read your density at stp (0 °c, 100 kpa) and the full breakdown beneath it.
Chlorine gas is about 2.5 times heavier than air, with a density of approximately 3.17 g/L at STP.
Frequently asked questions
- What is STP?
- Standard Temperature and Pressure. IUPAC redefined it in 1982/2010 as 0 °C (273.15 K) and 100 kPa. Older texts used 101.325 kPa (1 atm), giving V_m = 22.414 L/mol. This calculator uses the current IUPAC definition.
- Is this formula exact?
- Only for ideal gases. Real gases deviate, especially at high pressures or near their boiling points. For most gases at STP the deviation is < 0.1%.