Difference Between Straight and Branched Chain Alkanes

The key difference between straight and branched chain alkanes is that in straight-chain alkanes, all the carbon atoms bond with each other forming a continuous chain whereas branched-chain alkanes have side chains attached to a continuous carbon chain.

1. What is a branched alkane?
2. What is a straight chain alkane?
3. Why do straight chain alkanes have higher boiling points than branched?
4. Why are branched-chain alkanes more useful than straight chain?
5. How do you identify branched alkanes?
6. Why are carbon chains in alkanes not straight?
7. What are the 20 alkanes?
8. What are the first 10 alkenes?
9. What are the first 10 straight chain alkanes?
10. Why does boiling point decrease as branching increases?
11. Does branching increase stability?
12. Why do alkanes have higher boiling points?

What is a branched alkane?

Many hydrocarbons have branches of C atoms attached to a chain; they are called branched hydrocarbons. These branched alkanes are isomers of straight-chain alkanes having the same number of C atoms. However, they are different compounds with different physical and chemical properties.

What is a straight chain alkane?

An alkane is a hydrocarbon in which there are only single covalent bonds. These alkanes are called straight-chain alkanes because the carbon atoms are connected in one continuous chain with no branches. ... Naming and writing structural and molecular formulas for the straight-chain alkanes is straightforward.

Why do straight chain alkanes have higher boiling points than branched?

A straight-chain alkane will have a boiling point higher than a branched-chain alkane due to the greater surface area in contact, thus the greater van der Waals forces, between adjacent molecules.

Why are branched-chain alkanes more useful than straight chain?

Branched alkanes have a lower boiling point than straight chain alkanes due to the fact that they cannot pack together so well. Alkanes in general are quite unreactive. Their strong, non polar bonds make them unreactive to electrophiles, nucleophiles, acids, bases, oxidising or reducing agents.

How do you identify branched alkanes?

1. Count the longest continuous chain of carbons. ...
2. Number the carbons in the chain starting with the end that's closest to a branch. ...
3. Count the number of carbons in each branch. ...
4. Attach the number of the carbon from which each substituent branches to the front of the alkyl group name. ...
5. Check for repeated alkyl groups.

Why are carbon chains in alkanes not straight?

Free rotation is possible around the carbon-carbon single bonds in alkanes, making the carbon chains very flexible and "floppy" — particularly for the larger molecules. Alkanes are nonpolar molecules, since they contain only nonpolar carbon-carbon and carbon-hydrogen bonds.

What are the 20 alkanes?

Terms in this set (20)

• Methane. Ch4.
• Ethane. C2H6 (CH3CH3)
• Propane. C3H8 (CH3CH2CH3)
• Butane. C4H10 (CH3(CH2)2CH3)
• Pentane. C5H12 (CH3(CH2)3CH3)
• Hexane. C6H14 (CH3(CH2)4CH3)
• Heptane. C7H16 (CH3(CH2)5CH3)
• Octane. C8H18 (CH3(CH2)6CH3)

What are the first 10 alkenes?

The following is a list of the first 10 alkenes:

• Ethene (C₂H₄)
• Propene (C₃H₆)
• Butene (C₄H₈)
• Pentene (C₅H₁₀)
• Hexene (C₆H₁₂)
• Heptene (C₇H₁₄)
• Octene (C₈H₁₆)
• Nonene (C₉H₁₈)

What are the first 10 straight chain alkanes?

Terms in this set (10)

• methane. CH4 (C)
• ethane. C2H6 (C-C)
• propane. C3H8 (C-C-C)
• butane. C4H10 (C-C-C-C)
• pentane. C5H12 (C-C-C-C-C)
• hexane. C6H14 (C-C-C-C-C-C)
• heptane. C7H16 (C-C-C-C-C-C-C)
• octane. C8H18 (C-C-C-C-C-C-C-C)

Why does boiling point decrease as branching increases?

Branching decreases the boiling point

Van der Waals dispersion force is proportional to the surface area. ... Branching in molecules decreases the surface area thereby decreasing the attractive force between individual molecules. As a result, the boiling point decreases.

Does branching increase stability?

The branching, it seems, means that the electronic structure is simply more compact and this decreases molecular surface area per atom and so leads to a lowering of energy and a concomitant increase in stability.

Why do alkanes have higher boiling points?

Alkanes have low melting or boiling points because of the very weak intermolecular forces between alkane molecules. ... This means that there are more (relatively) stronger intermolecular forces between the molecules. As a result, it takes more energy to break these forces, and thus the melting or boiling points increase.