Calculate the volume of carbon dioxide produced by

Question

10cm³ of a gaseous hydrocarbon, CxHy, was reacted with 100cm3 of oxygen, an excess.  The final volume of the gaseous mixture was 95cm³.

The mixture was treated with concentrated, aqueous sodium hydroxide to absorb the carbon dioxide present. This reduced the gas to 75cm3. All gas volumes are measured at 298k and 100kPa.

• Calculate the volume of carbon dioxide produced by combustion of the hydrocarbon.
• Calculate the volume of oxygen used up in the reaction with the hydrocarbon.