<p>What volume of oxygen gas&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mfenced><msub><mi>O</mi><mn>2</mn></msub></mfenced></math>&nbsp;measured at&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML" class="wrs_chemistry"><msup><mn>0</mn><mo>&#176;</mo></msup><mi mathvariant="normal">C</mi></math>&nbsp;and 1 atm, is needed to burn completely 1L of propane gas&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mfenced><mrow><msub><mi>C</mi><mn>3</mn></msub><msub><mi>H</mi><mn>8</mn></msub></mrow></mfenced></math>&nbsp;measured under the same conditions?</p>