2 * 22.4 = 44.8 liters (if using pre 1982 standard)
2 * 22.7 = 45.4 liters (if using 1982 and later standard)
First, let's determine how many moles of F2 we have.
Atomic weight fluorine = 18.998403
Molar mass F2 = 2 * 18.998403 = 37.996806 g/mol
Moles F2 = 76 g / 37.996806 g/mol = 2.000168119 mol
Now we have a minor problem. What definition of STP are you using?
Up until 1982,
STP was defined as 0°C and 1 atmosphere (101.325 kPa)
From 1982 and later,
STP was defined as 0°C and 100 kPa
Because of the difference in pressure between the two different definitions of STP, the molar volume of a gas is 22.414 liter/mol using the pre-1982 definition and 22.711 liter/mol using the 1982 and later definition. So you get to choose which of the following 2 answers.
2 * 22.4 = 44.8 liters (if using pre 1982 standard)
2 * 22.7 = 45.4 liters (if using 1982 and later standard)
Unfortunately there's still a large number of text books in use using the standard that should have been obsolete 35 years ago.
