Answer:This might not help.
At STP, a 4.0-L flask contains 0.1784 moles of helium gas.
Step-by-step explanation:
At STP. temperature of the helium gas = T = 273.15 KAt STP, pressure of the helium gas = P = 1 atmVolume of the helium gas at STP = V = 4.0 L Moles of the helium gas = nUsing an ideal gas equation :n = 0.1784 mol0.1784 moles of helium gas are contained in a 4.0-L flask at STP.