What volume is occupied by 1.00 kg of helium at 5.00 degrees celsius at a pressure of 735 torr?

Well, we might as well convert all of this mess. ( we could work in Torr, but why when we are mass converting )

1.00 kg He (1000 grams/1 kg) = 1000 grams He (1 mole He/4.003 grams) = 250 moles He

5.00o Celsius = 278.15 Kelvin

735 Torr = (1 atm/760 Torr = 0.967 atmospheres

=========================================Now,

PV = nRT

(0.967 atm)(Volume) = (250 moles He)(0.08206 L*atm/mol*K)(278.15 K)

0.967V = 5706.247

Volume = 5.90 X 103 Liters

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