Ch.20 - Organic ChemistryWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds
Sections
Introduction to Organic Chemistry
Structural Formula
Chirality
Optical Isomers
Hydrocarbon
The Alkyl Group
Naming Alkanes
Naming Alkenes
Naming Alkynes
Alkane Reactions
Alkenes and Alkynes
Benzene Reactions
Functional Groups
Alcohol Reactions
Carboxylic Acid Derivative Reactions
Additional Practice
Stereoisomers
Organic Chemistry Nomenclature
Polymer

Like the other hydrocarbons, the alkynes also have a list of rules they must follow for naming. 

Naming Alkynes

Concept #1: Rules for naming Alkynes

Transcript

Hey guys! In this new video, we're going to take a look at naming alkynes. Naming alkynes is very similar to naming alkenes. Here we have to find the longest carbon chain, but now we change the -ane to -yne because we’re dealing with an alkyne. We change the -ane ending to -yne. Here, if there's more than one longest chain, go with the one that gives you more substituents. Just like with alkenes, here we’re going to count from the end closest to the triple bond and we have to state numerically where that triple bond starts.
Then with substituents, if there are same kinds of substituents around, then we talk about numerical prefixes. We’re talking about di, tri, tetra, and penta. Actually, let's take a look at this first one right now. Then I'll let you guys attempt example 2 on your own. Here: Name the following alkyne compound. Just like before, what I want you guys to do is look for the longest carbon chain.
And then remember, count from the end closest to the triple bond. Anything that's not part of the longest carbon chain is an alkyl substituent. Name that in the beginning of the name. State its location. State the location of the triple bond and you'll have the name of your structure. So guys, attempt to do this one. Come back and take a look at the video. Go over how exactly we name this first compound.

Example #1: Naming the following alkyne compound. 

Transcript

Alright guys! Let's attempt to name that example dealing with that alkyne structure. Hopefully, you were able to see that the longest carbon chain was this carbon chain and that we want to number from the end closest to the triple bond. That's 1, 2, 3, 4, 5, 6. We're going to stay here that we have a methyl group on carbon number 4. The name you should have gotten was 4-methyl. The triple bond starts after carbon 2, so 2-hex and it's no longer -ane. We change the -ane to -yne, so hexyne. That's the name you should have gotten.
Now that we've done this, attempt to do this one here. Here I'm going to give you guys a lot of help. When we say phenyl, phenyl is when benzene is a substituent. Benzene as a substituent. Recall, what does benzene look like again? How exactly does it fit into this compound? Start with the end of the name to help you draw it. Come back and see how I draw this compound.

Example #2: Provide the structural formula from the following alkyne name.

4–phenyl–2–nonyne

Additional Problems
NAMING ALKYNES Naming an alkyne is similar to naming an alkane with a few differences. Find the longest carbon chain and change the “ane” ending to “yne”. If there is a tie between longest chains, choose the chain that gives the _________ substituents. Number the chain from the end closest to the triple bond and provide a number for its location. Substituents will be named alphabetically and a number will accompany the location of their attachment. If more than one of a similar alkyl group is present then we must use numerical prefixes to describe the number of them.             __________ – 2         __________ – 3         __________ – 4         __________ – 5  
NAMING ALKYNES Naming an alkyne is similar to naming an alkane with a few differences. Find the longest carbon chain and change the “ane” ending to “yne”. If there is a tie between longest chains, choose the chain that gives the _________ substituents. Number the chain from the end closest to the triple bond and provide a number for its location. Substituents will be named alphabetically and a number will accompany the location of their attachment. If more than one of a similar alkyl group is present then we must use numerical prefixes to describe the number of them.             __________ – 2         __________ – 3         __________ – 4         __________ – 5    
Provide the structural, condensed or skeletal formula for the following:  a) 4-methyl-1-hexyne     b) 3,3-diethyl-1-oxtyne  
Provide the structural, condensed or skeletal formula for the following:  a) 4,4,5-trichloro-2-heptyne       b) 4-bromo-1-chloro-4-methyl-2-nonyne
An organic compound contains 3 carbon atoms and one triple C≡C bond would have the name of: a) Propane b) Pentene c) Propyne d) Pentyne
Name the following alkyne.
Alkanes are named using the ane ending, and with prefixes to indicate the number of carbon atoms in the longest carbon chain. For example, CH4 is called methane. Alkenes are named using the ene ending. The position of the double bond is indicated with a number designating the position of the bond in the carbon chain. The numbering starts at the end of the carbon chain closest to the double bond. For example, CH3CH=CHCH2CH3 or CH3CHCHCH2CH3 (or CH3CH2CH=CHCH3 and CH3CH2CHCHCH3)is called 2-pentene. Alkynes are named in a manner similar to the alkenes but using the yne ending. For example, CH3C≡CCH3 or CH3CCCH3 is called 2-butyne.The roots used to indicate the number of carbon atoms are given in the table below:Number of C atoms12345678910Root namemethethpropbutpenthexheptoctnondec a. What is the name of the following organic compound?CH3CH2CH2CH2CH2CH2CH2CH3b. What is the name of the following organic compound?CH3CH2CCCH2CH2CH3c. What is the chemical formula of 4-nonene? Express your answer as a chemical formula.
Name the following compound: