Rank the homologous series for a set of alkanes by their boiling point? the boiling points for a set of compounds in a homologous series can be qualitatively predicted using intermolecular force strengths. using their condensed structural formulas, rank the homologous series for a set of alkanes by their boiling point.
rank these alkanes from highest to lowest boiling points
; the correct answer is heptane 3,3-dimethylpentane hexane butane. though, your tip !

Alkanes from highest to lowest boiling points:

1. heptane2. 3.3 dimethyl pentane3. hexane4. butaneFurther explanation

Alkanes are saturated hydrocarbons with all carbon bonds being single bonds

General formula:

There are several rules for naming alkanes from IUPAC:

the name of the branch followed by the name of the main chain the main chain is the longest chain that has the most branches branches are given the name alkyl with the symbol -R, and begin with a number, with the position of the branch getting the smallest number more than one branch is prefixed in, tri, tetra, penta, etc. and in alphabetical order with the smallest number.

In determining the alkane boiling point, if in the same homologous series, then just look for alkanes with the largest relative molecular mass that will have a large boiling point too. So in an alkane in the form of a straight-chain, the more carbon atoms, the longer the main chain, the bigger the boiling point.

But if the relative molecular mass is the same, the alkanes have fewer branches will have a greater boiling point.

The more branches, the lower the boiling point, even though the number of carbon atoms is the same (as in isomers)

In isomers that have the same molecular formula and relative molecular mass, alkanes that have the fewest branches will have the largest boiling point.

So that the general determination of the alkane boiling point is (based on its priority)

1. relative molecular mass

the greater the higher the boiling point

2. main chain branch

the fewer branches the higher the boiling point

The branching on the main chain in the alkane structure causes the attraction between the molecules to be lower so that to release this attractive force only requires low energy, ie at low temperatures

The relative molecular mass of each alkane in the above problem is:

1. heptane: 1002. 3.3 dimethyl pentane: 1003. hexane: 864. Butane: 58

The relative molecular mass values above indicate that there are similarities in the relative molecular mass values of heptane and 3.3 dimethyl pentane. But because the unbranched chain has a higher boiling point so heptane has a greater boiling point than 3.3 dimethyl pentane

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the name of this hydrocarbon

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 the correct name of the compound

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type of organic compound contains the following functional group

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Keywords: alkanes, main chains, branches, boiling points, relative molecular mass

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