11. If the density of a certain gas at 30°C and768 torr is 1.35 kg/m3

1.	11. If the density of a certain gas at 30°C and768 torr is 1.35 kg/m3 its density at STP would be
Answer» Let us assume that V = 1 liter. PV = nRT n = PV/RT = (768/760 atm) x (1 L) / [(0.0821 Latm/mole K) x (303K)] = 0.0406 moles of gas = 1 L x (1 m³ / 1000 L) x (1.35 kg / 1 m³ ) x (1000 g / 1 kg) = 1.35 g Thus, MW of gas = 1.35 g / 0.0406 moles = 33.3 g/mole. At STP,n = PV / RT = (1.0 atm) x (1 L) / [(0.0821 Latm/moleK) x (273K)] = 0.0446 moles = 0.0446 moles x (33.3 g / mole) x (1 kg / 1000 g) = 0.00149 kg = 0.00149 kg / 1 L x (1000 L / 1 m³) = 1.49 kg / m³ bro bt smjh nhi aaya..3rd step k bd

11. If the density of a certain gas at 30°C and768 torr is 1.35 kg/m3 its density at STP would be

Answer»

Let us assume that V = 1 liter.

PV = nRT

n = PV/RT = (768/760 atm) x (1 L) / [(0.0821 Latm/mole K) x (303K)] = 0.0406 moles of gas

= 1 L x (1 m³ / 1000 L) x (1.35 kg / 1 m³ ) x (1000 g / 1 kg) = 1.35 g

Thus, MW of gas = 1.35 g / 0.0406 moles = 33.3 g/mole.

At STP,n = PV / RT = (1.0 atm) x (1 L) / [(0.0821 Latm/moleK) x (273K)] = 0.0446 moles

= 0.0446 moles x (33.3 g / mole) x (1 kg / 1000 g) = 0.00149 kg

= 0.00149 kg / 1 L x (1000 L / 1 m³) = 1.49 kg / m³

bro bt smjh nhi aaya..3rd step k bd