We can use gas laws to determine the number of moles of gas in a 168L tank at STP (Standard Temperature and Pressure).
Step-by-step explanation:
At STP, one mole of gas occupies 22.4 L. Therefore, to find the number of moles (n) of gas in a 168L tank, we can use the following formula:
n = V / VM
where V is the volume of the gas and Vm is the molar volume at STP.
Substituting the values:
n = 168 L / 22.4 L/mol
Calculating the result:
n ≈ 7.5 mol
Answer: Therefore, approximately 7.5 moles of gas are in a 168L tank at STP.