Which choice is a pair of isomers? view available hint(s) which choice is a pair of isomers? ch3ch2ch2ch3 and ch3ch(ch3)2 ncch3 and ch3cn ch3oh and ch3och3 1-pentene and 2-methylbutane butanol and propene?

Easy to understand all the pairs of compounds are drawn below,

            Option-A (Butane and 2-Methyl propane)
                                         &
            Option-D (Pentane and 2-Methyl butane)

are the isomers of each other.

Explanation:
                   Isomers are those compounds which have same molecular formula but different structural formula.

In given options, Option-B are not isomers because they are the same compounds, just flipped on 180°.

Option-C are not isomers because the number of carbo and hydrogen atoms are not same.

Option-E are not isomers because the number of hydrogen, carbon and oxygen atoms are not same.

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