Based on the molecular formula, determine whether each compound is an alkane, alkene, or alkyne. (Assume that the hydrocarbons are noncyclical and there is no more than one multiple bond.)

a. C₅H₁₂ b. C₂H₂ c. C₇H₁₄ d. C₁₁H₂₂

Video transcript

Welcome back, everyone classify the molecular formerly as Alkanes Alkins or Alkins note, it is assumed that these are a cyclic and they can contain only one double bond or triple bond. And we are given four structures. What we want to recall in this problem is the molecular formula of each structure. Specifically, we are considering the general molecular formulas. If we have an L cane, it would have a molecular formula of CNH two N plus two. Where N is a natural number. Specifically, we can take NS +123 and so on. For L KS, we are going to look at CNH two N. So we have a twice greater number of hydrogens. And for L kinds, it will be CNH two N minus two. So let's say we'll look at the first part of the problem that's C five H 10, our N is five because we have a total of five carbon atoms. And we can immediately see that the number of agens is twice as large, right. So two N is simply 10. The molecular formula is C five H 10 is essentially equal to CNH two N, one N is equal to five. And therefore, it essentially corresponds to an LK with the general formula CNH two N. So the first structure is an LK moving on to number two, we have C three H four, our N is three, if we double that two N would be six, and we have a lower number. Specifically, it's four. Now to get four, we simply need to subtract two from six. So we have two and minus two, which gives us four. And the general formula of C three H four is therefore CNH two and minus 21 N is equal to three. And that's an LK number three. The given molecular formula is C 614. And based on this formula N is six. What if we multiply that by two, two N is 12? And we have a greater number specifically, we have two M plus two which gives us 12 plus two is 14, right? Therefore, C six, age 14 corresponds to the formula CNH two N plus two, one N six. And that general formula corresponds to an al kin. And finally, we can consider structure number four, C three H six. Our N is three if we multiply that by 22 and a six and that's exactly what we have. So it's C three H six is equal to CNH two N, one end is three. And that molecular formula corresponds to an L kin. So let's label our answers. Now, the first structure corresponds to an L Kin, the second one to an Al Kine, the third one to nlk and the fourth one to an A king. Thank you for watching.