Texts 1 when 3705 grams of a hydrocarbon cxhy were burned in...

Texts: 1. When 3.705 grams of a hydrocarbon, CxHy, were burned in a combustion analysis apparatus, 12.53 grams of CO2 and 2.564 grams of H2O were produced. In a separate experiment, the molar mass of the compound was found to be 26.04 g/mol. Determine the empirical formula and the molecular formula of the hydrocarbon. 2. When 4.846 grams of a hydrocarbon, CxHy, were burned in a combustion analysis apparatus, 16.64 grams of CO2 and 2.725 grams of H2O were produced. In a separate experiment, the molar mass of the compound was found to be 128.2 g/mol. Determine the empirical formula and the molecular formula of the hydrocarbon. 3. A 6.896 gram sample of an organic compound containing C, H, and O is analyzed by combustion analysis and 17.40 grams of CO2 and 3.053 grams of H2O are produced. In a separate experiment, the molar mass is found to be 122.1 g/mol. Determine the empirical formula and the molecular formula of the organic compound. (Enter the elements in the order C, H, O.) Please find the empirical formula and the molecular formula. Thank you!

Transcript

00:01 Hello students welcome here in this question we have two parts are there so the first part in organic compound is having the molar normal mass is 10 .69 grams so it is a combustion reaction analysis is given so here 19 .06 grams of co2 is produced and 7803 grams of h2 is produced.

00:31 So we had to calculate the empirical formula and molar mass is given here 74 .08 grams per mole.

00:40 So molar mass is given that means we had to calculate both empirical formula and molecular formula of the compound.

00:48 Okay, so first of all we will calculate the number of moles of carbon.

00:53 So the number of moles of carbon is equal to number of moles of co2 because the total number of carbons are present in the compound is equal to the total number of carbons present in carbon dioxide so that's why here in mass is given 90 .06 and carbon dioxide has the molar mass is 44 .019 moles.

01:27 So that is equal to 0 .4330 moles of carbon is there.

01:34 So what is the mass of this one is we will calculate mass also.

01:40 Number of moles we have and mass of carbon is equal to carbon is equal to 0 .433 multiplied by 12 .01.

01:55 So that is equal to 5.

01:56 2 .203 grams of carbon is present.

02:02 Now, number of moles of hydrogen.

02:04 Number of moles of hydrogen is equal to 2 multiplied by number of moles of h2.

02:17 Because one molecule is containing two atoms of hydrogen.

02:21 That's right.

02:22 So that is equal to the given molar, the given mass is here 7 .80.

02:27 3 9 divided by 18 .029 is a molar mass of water.

02:33 So that is equal multiplied by 2.