Question

Why in this propane is used even though it is attached to 4 carbon
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Answer 1

Answer:

Thus, the word "propane" indicates that there are three carbon atoms in the chain, all connected by single bonds. ... As the number of carbon atoms increases, the number of structural isomers increases rapidly (see butane and isobutane below for examples).

Explanation:

Carbon has two electron shells, with the first holding two electrons and the second holding four out of a possible eight spaces. When atoms bond, they share electrons in their outermost shell. Carbon has four empty spaces in its outer shell, enabling it to bond to four other atoms

Answer 2

Answer:

Explanation:

Thus, the word "propane" indicates that there are three carbon atoms in the chain, all connected by single bonds.

Number of

Carbons Stem

1 meth-

2 eth-

3 prop-

4 but-

5 pent-

6 hex-

7 hept-

8 oct-

9 non-

10 dec-

For branched chains, the name of the longest continuous chain of carbon atoms is preceded by the names of the carbon substituents, which are named as alkyl groups (#C prefix + -yl); a position number is placed in front of the alkyl group name to indicate which carbon of the longest chain the alkyl group is attached to. If there is more than one of the same type of alkyl group, their names are combines into a single word, prefixed by a counting prefix (2 = di, 3 = tri, 4 = tetra, 5 = penta, etc.), and preceded by location numbers for each group.  Thus, the name "2-methylpropane" indicated that there is a three-carbon longest chain, with a one-carbon branch on the second carbon; the name "2,3-dimethylbutane" indicates that there is a four-carbon longest chain, with two one-carbon substituents on carbons 2 and 3.

Some molecules of the same molecular formula can have their atoms arranged in a different order; we say that these molecules are structural isomers of each other.  The simplest alkanes have only one way in which their atoms can be arranged, and have no structural isomers.  As the number of carbon atoms increases, the number of structural isomers increases rapidly (see butane and isobutane below for examples).