Question #8bc4e

1 Answer
Jan 1, 2016

Indeed, the compound's molecular formula is "C"_16"H"_34.

Explanation:

All you have to do here is use the concept of mass conservation to figure out how many moles of carbon and how many moles of hydrogen were a part of the original compound.

As you know, cracking is simply a process used to split complex organic compounds into simpler molecules by breaking carbon - carbon bonds.

This means that after the cracking takes place, the number of atoms that were a part of compound "Y" must now be a part of the three listed products.

Your strategy here will be to list the products that result from the cracking of your compound "Y"

  • two moles of ethene, "C"_2"H"_4
  • one mole of 1-butene, "C"_4"H"_8
  • one mole of octane, "C"_8"H"_18

and figure out how many moles of carbon and of hydrogen were produced. You will have

"For C: " overbrace(2 xx 2)^(color(red)("from ethene")) + overbrace(1 xx 4)^(color(blue)("from 1-butene")) + overbrace(1 xx 8)^(color(green)("from octane")) = "16 moles C"

color(white)(x)

"For H: " overbrace(2 xx 4)^(color(red)("from ethene")) + overbrace(1 xx 8)^(color(blue)("from 1-butene")) + overbrace(1 xx 18)^(color(green)("from octane")) = "34 moles H"

So, one mole of compound "Y" contained 16 moles of carbon and 34 moles of hydrogen. This of course means that one molecule of compound "Y" will contain 16 atoms of carbon and 34 atoms of hydrogen.

Therefore, the compound's molecular formula will be

"C"_16"H"_34 -> hexadecane

![https://en.wikipedia.org/wiki/Hexadecane](useruploads.socratic.org)