Question

Question #5018b

Answer 1

`"16.0 g"`

Explanation:

STP conditions are usually given as a pressure of `"1 atm"` and a temperature of `0^@"C"`. Under these conditions, `1` mole of any ideal gas occupies `"22.4 L"` `->` this is known as the molar volume of a gas at STP.

Using the molar volume of a gas at STP, you can calculate the number of moles of oxygen gas present in your sample

`11.2 color(red)(cancel(color(black)("L"))) * "1 mole O"_2/(22.4color(red)(cancel(color(black)("L")))) = "0.50 moles O"_2`

To convert this to grams, use the molar mass of oxygen gas

`0.50 color(red)(cancel(color(black)("moles O"_2))) * "32.0 g"/(1color(red)(cancel(color(black)("mole O"_2)))) = color(darkgreen)(ul(color(black)("16.0 g")))`

The answer is rounded to three sig figs, the number of sig figs you have for the volume of oxygen gas.