posted by Perry on .
The chemical substance in natural gas is a compound called methane. Its molecules are composed of carbon and hydrogen and each molecule contains four atoms of hydrogen and one atom of carbon. In this compound, 0.33597g of hydrogen is combined with 1g of C12. Use this information to calculate the atomic mass of the element hydrogen.
Please explain each step thoroughly, thanks in advance!
first we write the balanced chemical reaction:
C + 2 H2 -> CH4
*note that Hydrogen is diatomic in nature (that's why it's H2, not H)
then to get how much H2 reacted (in grams), we use the data of Carbon. 1 g of Carbon reacted, thus to get the number of moles of C, we divide 1 g by its molar mass (which is 12 g/mol)
1/12 = 0.0833 mol C
using the stoichiometric coefficients (number before the chemical symbol in the reaction) of the elements, we can relate the number of moles of C reacted to the number of moles of H2 reacted:
0.0833 mol C * (2 mol H2 / 1 mol C) = 0.1667 mol H2
then from the given, 0.33597 g of H is used. to convert this to grams of H2, we just divide 0.33597 by 2:
0.33597 g H / 2 = 0.167985 g H2
finally, to the the molar mass of H, we divide grams of H2 by moles of H2:
0.167985 / 0.1667 = 1.01 g/mol
hope this helps~ :)