# How to convert pressure in mm Hg to atm & psi & calculate pressure using Pv= nRT equation

1. Typical atmospheric pressure on Mt. Everest (29,028 ft.) is 235 mm Hg. Convert this pressure to atm and psi

2. A 5.90 L bottle contains 1070 g of oxygen at 25.0 °C. Calculate the pressure (in atm) inside the flask.

3. A sample of helium gas occupies 9.50 L at -11.0 °C. and 0.970 atm. Calculate the volume the helium gas will occupy at 50.0°C and 1.15 atm.

### 1. Typical atmospheric

1. Typical atmospheric pressure on Mt. Everest (29,028 ft.) is 235 mm Hg. Convert this pressure to atm and psi

To do this you need to know the conversion factors:

760 mm Hg  =  1.00 atm    and      760 mm Hg  =  14.7 psi

235 mm Hg   x     1.00 atm/ 760 mm Hg     =       ______________ atm   (I'll leave the arithmetic to you)

235 mm Hg   x     14.7 psi / 760 mm Hg     =        ______________ psi

2. A 5.90 L bottle contains 1070 g of oxygen at 25.0 °C. Calculate the pressure (in atm) inside the flask.

Convert the mass of oxygen to moles (Don't forget oxygen is O2).

Use the Ideal Gas Equation     PV = nRT  and solve for P

P =  n R T / V      (Make sure you convert your C temp to Kelvin)

3. A sample of helium gas occupies 9.50 L at -11.0 °C. and 0.970 atm. Calculate the volume the helium gas will occupy at 50.0°C and 1.15 atm.

Use the combined gas law:   P1  V1  / T1    =   P2  V2 / T2 (make sure Temps are in Kelvin).

### Use the following

Use the following relationship for mmHg to psi conversion
1 mm Hg = 1 Torr
1 Psi = 51.7149326 Torr

For mmHg to atm conversion
1 mm Hg = 1 Torr
1 atm = 760 torr

2. PV = n RT

From given mass of oxygen find the number of moles, Volume and temperature is Given, make sure to convert temperature to kelvin

3.Use, p1v1/T1= p2v2/T2