## 7.9 Torr and atm conversions

$\Delta U=q+w$

Hannah Pablo 2H
Posts: 10
Joined: Fri Sep 26, 2014 2:02 pm

### 7.9 Torr and atm conversions

Problem: A gas in a cylinder was placed in a heater and gained 5500 kJ of energy as heat. If the cylinder increased in volume from 345 mL to 1846 mL against an atmospheric pressure of 750. Torr during this process, what is the change in internal energy of the gas in the cylinder?

Could someone please explain the Torr and atm part of this problem?

Niharika Reddy 1D
Posts: 127
Joined: Fri Sep 26, 2014 2:02 pm

### Re: 7.9 Torr and atm conversions

You can convert the atmospheric pressure into atm by using the conversion factor 1 atm=760 torr. After calculating the change in volume, find the amount of work by using w=-PΔV and add this to the heat to get the change in internal energy.