Answer:
2.77 atm
Step-by-step explanation:
The total pressure of a mixture of gases is calculated as the addition of the partial pressures of the gases. In this case, the total pressure (Pt) is calculated from the partial pressures of helium (PHe), nitrogen (PN₂) and neon (PNe):
Pt = PHe + PN₂ + PNe
First, we have to convert the partial pressures to the same unit (atm). For this, we have to know that 1 atm=760 mmHg=760 Torr
PHe = 585 mmHg x 1 atm/760 mmHg = 0.77 atm
PN₂= 0.76 atm
PNe= 940 Torr x 1 atm/760 Torr = 1.24 atm
Finally, we calculate the total pressure in atm:
Pt = 0.77 atm + 0.76 atm + 1.24 atm= 2.77 atm