Question

How many liters of oxygen would be needed to produce 45.0 liters of carbon dioxide if the temperature and pressure for both are 22.0° C and 75.0 psi?

Answer 1

A precise volume of `45` `L`.

Explanation:

At constant pressure, and constant temperature, equal volumes of gases contain an equal number of molecules; this is [Avogadro's law of combining volumes.](http://www.chemistry.co.nz/avogadro.htm)

Given that reaction has `1:1` stoichiometry, i.e.

`C(s) + O_2(g) rarr CO_2(g)`

If `45` `L` of oxygen were used, stoichiometry insists that `45` `L` of carbon dioxide were produced. This is a good thing, because using mixed units in questions like this (i.e. `"litres"` and `"pounds per square inch"`) is simply asking for trouble.