 Okay, so let's try this one. It says how many distinct chloropentanes and then it gives you the molecular formula C5H11Cl Could be produced in the direct chlorination of n-pentane CH3CH23CH3 and then I want you to draw the structure of each molecule. So the cool thing is that we've got pentane here and and it's actually being reacted with chlorine under conditions like that to produce a series of chloropentane. So it's not wanting you to draw all of the isomers with this particular formula. Just want you to go from normal pentane to what you could get, okay? So we have a model of normal pentane here, or n-pentane. So if you guys remember it's just the straight chain, right? So five carbons in a row fully saturated and that's given to you here. Okay, so if we let's just draw that chlorinated product because it gives us this molecular formula here, okay? So what we know these chloropentanes is if we take pentane right, we take pentane and we replace one of the hydrogens with a chlorine like we've done here. We do it on the end, right? This thing can spin around, right? We can fully rotate around single bonds like that, okay? So no matter which one of those hydrogens we replace, we get the same molecule. Does everybody understand that? Does that make sense to you guys? Does that make sense? Okay. So in other words, then we're going to replace like a hydrogen with a chlorine. We could replace any one of those three hydrogens when we get the same molecule, okay? So let's go ahead and just replace one like that. So that's one of the chloropentanes. In fact, I'm going to put our lone pairs there because we remember about the lone pairs, right? Okay, the other cool thing is so remember we took pentane here and we replaced one of the hydrogens on the end, this end, right, with a chlorine, okay? But watch what happens. If I turn this around, that's like replacing one of these hydrogens with a chlorine. Does that make sense? So in fact, if I replace either one of these or one of these, I get the same compound because I can turn this thing around, right? And I'm not breaking any single bonds. I'm not making any single bonds anymore, right? So if I do that, then that means that I'm not making a chemical reaction occur, right? So if I replace one of the hydrogens here, that means it's the same as replacing one of the hydrogens here. So we don't want to write an isomer that has a C all over here, okay? So let's just go down the line. Okay, we've done this one. So let's write pentane again. So essentially what we're doing is looking for equivalent hydrogens, if you remember that concept, right? Okay, so if you think about pentane, these three hydrogens are equivalent and these three hydrogens are equivalent to these three hydrogens as well, okay? So we have six equivalent hydrogens there. So any one of those we replace, we get the same compound. Okay, so let's move on to the next one, the next carbon here. So remember we have pentane here. What are we doing? We're replacing this hydrogen here with a chlorine. So we've got that. Remember we can spin around the single bond, okay? So that means these two hydrogens are the same kind of in the same area, right? So if I replace either one of those, I get the same compound, okay? So let's just erase that, put a seal there. So I've replaced here, right? If I turn this around, then I get the same thing as if I would have replaced the seal here. So in fact, we have equivalent hydrogens on the end here, right? So six equivalents, and we have four equivalents in the actual pentane structure. So if we look at pentane, right? These two hydrogens are equivalent, but they're also equivalent to these two hydrogens here, okay? So just to make sure, right, that we understand, right? If I turn this around, it's not like I'm breaking any single or double bond or single bonds or making any single bonds, okay? So that would be one. So if I'm drawing this one, remember not to put a seal over here, okay? And then we just move one over, and we see we've got two equivalent hydrogens, right? There's no carbon that looks like that carbon, okay? So we're going to, let's drop pentane again. So let's just replace one of those with a seal. So this is pentane. It's like replacing one of those two with a seal. So let's do that. Replace that one. It's the same as replacing the other one, okay? But it's not the same as replacing any other hydrogen here, okay? So if this is the answer to the question, these are the three isomers that you could get, the three chloropentane or N-chloropentane isomers that you could get. This one's called one chloropentane. This one's called two chloropentane. This one's called three chloropentane, okay? So let's write that down. And let's go back and just one more time write out pentane, and then we'll find ourselves at the end which hydrogens are equivalent to each other, okay? So hydrogens that are all labeled A are going to be equivalent to each other. So HA, HA, HA. Those three are HAs. So are these three? Okay, so if I replace any one of those, I get the same compound as replacing any of the other ones. So which ones are HB? Like that. And then on this side too, just like you see. And then these ones would be then what? HC. Okay, so notice I could only get this compound by replacing one of those two. I could get this compound by replacing any one of those four. And I could get this compound by replacing any one of those six, okay? Be clear on that? So that would be like three chloropentane. That would be like two chloropentane, right? And this would be like one chloropentane. So I could replace any of the three, right? So it would be the same. Or I could replace any of these three too, because that would be the same too, okay? Questions on that? Wonderful.