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Density of a Gas at STP. Density of a Gas at STP. The densities for most substances are measured in units of g/cm 3 or g/mL . However, the density of gases is usually measured in units of g/L . WHY? Because the amount of gas in 1 cm 3 is so small!
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Density of a Gas at STP • The densities for most substances are measured in units of g/cm3 or g/mL. • However, the density of gases is usually measured in units of g/L. • WHY? • Because the amount of gas in 1 cm3 is so small! • On Reference Table S, the density for helium is given as 0.000164 g/cm3 at 298K and 101.3 kPa. 0.000179 g/cm3 = 0.179 g/L
Density of a Gas at STP Copper cube Is right here! A 0.000446 L cube filled with 4.00 g copper at STP A 22.4 L balloon filled with 4.00 g helium gas at STP
Density of a Gas at STP Ex. (1) What is the density of a gas with a mass of 6.45 g and a volume of 5.00 L? d = m V X = 6.45 g 5.00 L = X 1.29 g/L
Density of a Gas at STP Ex. (2) What is the density of Xe gas (in g/cm3) at 298 K and 101.3 kPa? d = m V d = 0.005366 g/cm3
Density of a Gas at STP Ex. (3) What would be the volume of 3.926 g of methane gas (d = 0.716 g/L) at STP? d = m V 0.716 g/L = 3.926 g 1 X = X 5.48 L
Density of a Gas at STP Ex. (4) What is the mass (in grams) of 112 cm3 of argon gas at 298 K and 101.3 kPa? d = m V 0.001633 g/cm3 = X 1 112 cm3 = X 0.183 g