Condensed Formula - Video Tutorials & Practice Problems

Condensed Formula Concept 1

Now condensed formula shows how the atoms in a compound are bonded without showing all the bonds. Now, carbon and hydrogen atoms are grouped together in blocks. So what I mean by that is we have CH three where the three hydrogens on the compounds are packed together, grouped together, ch two, the two hydrogens on the carbon are grouped together and then ch the carbon and the hydrogen are grouped together. If we take a look here, we have our structural formula here. Our structural formula shows all the bonds being created between our atoms. We're showing the car all the carbon carbon bonds and all the carbon hydrogen bonds. Now with condensed, we would package in this ch three. So bring in those three hydrogens and the reason we draw backwards like this is to show that it's the carbons that are connecting to each other and not hydrogen to carbon. Because if we wrote it this way, it would almost look like my three hydrogens are connecting to my carbon. But they're not, it's the carbons that are connected to each other. Here, we have our CH two. So bring in those two hydrogens with the carbon So we have CH two here and then here on the right end, here we have CH three again, bring in those three hydrogens to give us CH three. Now we can go even further and and condense it even more by erasing those bonds that show the carbon carbon linkages. So here I erase this bond and this bond and just bring everything in closer. So my fully condensed formula would be CH three, ch two ch three. So this is how we go from our structural formula to our condensed formula.

Condensed Formula Example 1

Here, it says, draw condensed formula for a compound with the mole following molecular formula C 4h 10. Here we're given a hint, arrange all carbon atoms in a row. All right. So we'd have our carbons, all connected to each other are four carbons. And remember, carbon wants to make four bonds. And in order to do that, we distribute hydrogens to all of them. So this here represents my structural formula where I'm showing each of the bonds between carbon carbon and carbon hydrogens. But remember we want to condense. So now we package things in here. We have a carbon connected to three hydrogen. So that's CH three. Then we have carbon connected to two hydrogens at C two again, another CH two. And then finally, we have a carbon connected to three hydrogens. Again, that'd be ach three. So this will represent our condensed formula CH three, ch two, ch two ch three. This would be our final answer.

Parenthesis and Parenthesis w/ Subscripts Concept 2

In this video, we're gonna talk about condensed formulas, including parentheses and parentheses with subscripts. So here we're going to say that groups that are in parentheses are branches or brands structures. So for example, we have CH three here, if we take a look at the structural formula, we see that we have these three carbons here in a row together and branching off of that middle carbon is our CH three group. Now, if we can, if we change the structural formula into our condensed formula, we'd start out by saying we have ach three group here, which is shown here that then comes after that ach group right here, branching off of that CH group is our CH three group up here to designate it as a branched structure. We put it in parentheses and then we continue down our chain after the CH is our CH three. So after this branched group here, branch structure, we write CH three. So as our molecules or compound become more and more complex, we're gonna sometimes need to utilize parentheses to talk about the branched structures coming off of my main chain, right. So this is just one way we can illustrate that this CH three in this particular structure represents a branched structure, right. So we're gonna start doing more, more complex ones and we're gonna incorporate more, more parentheses.

Condensed Formula Example 2

Here it says, write a condensed formula for the following compound. So here we have CH three connected to AC which contains a seal coming off of it. That CH is connected to another CH that has a BR coming off of it. And then we end with another CH three. So how would we write this? Well, we're gonna have our CH three to start that's connected to our C A troop. Remember we put, we use parentheses to show our branch branches that CL is a branch. So we put parentheses, CL then we have another CH which has its own branch of BR. So in parentheses, and then we conclude it with RCH three. So this will represent our condensed formula with our two branches of chlorine and Bromine.

Condensed Formula with Subscript Concept 3

In our continued discussion of condensed formulas. Now we take a look at parentheses with subscripts in this case, they indicate repeating units. So for example, CH two, if we take a look at the structural formula of this hydrocarbon, we have what CH three CH two CH two CH three. If we want to convert this to condensed, we learned that we could have done CH three and then we could do CH two CH two and then CH three. But we can further condense this even more. We're gonna say that these two CH twos in the middle, we can combine them even more, putting them in parentheses and then putting a little subscript at the bottom tells me that there are two CH twos in the middle of this hydrocarbon. So here this would be another version of a condensed formula where we have now repeating units.

Condensed Formula Example 3

In this example question, it says draw a structure for the following condensed formula. Here we have CH three and then in parentheses CH two and then a subscript of three followed by CH three again. So here we're going to say we're starting out with CH three. So we have a carbon connected to three hydrogens. It is now connected to three of these CH twos. So we're gonna have CH two here in the middle, another CH two here in the middle. And then finally, our third CH two here in the middle, that last one is connected to the CH three at the end. So this would represent our structural formula when given this condensed formula.

Write a condensed formula for the given structure.

• A. CH₃CH(CH₃)CH(NH₂)CH₃
• B. C₅H₁₃N
• C. CH₃CH(CH₂)CH₃(NH₂)CH₃
• D. (CH)₂(CH₃)₃NH₂

Convert CH₃(CH₂)₂CHBrCH₃ into structural formula.

• A.
• B.
• C.
• D.