A sample of a hydrocarbon is combusted completely in O21g2 to produce 21.83 g CO21g2, 4.47 g H2O1g2, and 311 kJ of heat. (a) What is the mass of the hydrocarbon sample that was combusted?

Video transcript

Hi everyone. So we have a complete combustion of a hydrocarbon producing 7.2 g of carbon dioxide and 2.45 g of H 20. And the heat given off is 463 kg jewels. Were asked to determine the mass of the substance and busted. Do we know that a hydrocarbon contains hydrogen and carbon? So the first thing we need to do is find the mass of the carbon, The mass of carbon dioxide and then find the mass of hydrogen from the mass of H 20. Have 17.2 grams of carbon dioxide. And in one mold of carbon dioxide we have the molar mass And this is 12.011 g. Us too. I'm 15 .999 g. Just give us 44 01 g and one more of carbon dioxide have one mole of carbon and in one more of carbon. The massive carbon 12.011 g They get 4.69 grams of carbon, 2.45 Fans of H 20. In one more of H 20 have the molar mass. And this is to 1.008g. That's 15 .999 g. We get 18.02 g. And in one more Of H 20. I have two malls of hydrogen And then one more of hydrogen. The maths which is 1.008g. We get 0.27 grams of hydrogen. So now we need to add up the masses of carbon and hydrogen to determine the mass of the substance, We have 4.69 g 0.27 g. I get 4.96 g. Thanks for watching my video, and I hope it was up for.