A 0.216 g sample of an aluminium compound X reacts with an excess of water to produce a single hydrocarbon gas. This gas burns completely in O2 to form H2O and CO2 only. The volume of CO2 at room temperature and pressure is 108cm3. What is the formula of X

0.216g of aluminium compound X react with an excess of water water to produce gas. this gas burn completely in O2 to form H2O and 108cm^3of CO2 only. the volume of CO2 was measured at room temperature and pressure

0.108 / n = 24 / 1

n = 0.0045 mole (CO2 >>0.0045 mole

0.216 - 0.0045 = 0.2115

so Al = 0.2115 / 27 = > 0.0078 mole

C = 0.0045 * 1000 = > 4.5 and Al = 0.0078 * 1000 = 7.8