What gas law do I use? Step by step how is this done? I missed the class and the book doesnt do a good enough example to help me understand.

### 2 Answers

Use PV = nRT, where P is pressure, V is volume, n is moles, R is gas constant, T is temp in K

so rearrange the equation to read V = (nRT) / P

plug in what you know.

Calculae the mol of O2 in 5.60 g of O2 n = m / M 5.60 g / 32 g/mol = 0.175 mol

`V = (0.175 x 0.08205 x 415) / 7.78 V = 0.769 L`

`use PV = nRT`

convert the 5.60g to moles

use 0.0821 for R and solve for V in liters