Question

What volume measured in stp will 3.75 grams of helium gas occupy?

Answer 1

Molar mass helium gas :

He = 4.0 g/mol

number of moles: 3.75 / 4.0 => 0.9375 moles

1 mole ------ 22.4 ( at STP)
0.9375 ------ ?

volume = 0.9375 x 22.4 / 1

Volume = 21 / 1

Volume = 21 L

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