List the general characteristics of the homologus series? and Define structural isomers?

Answer 1

In chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group, and shows a gradation in physical properties as a result of increase in molecular size and mass (see relative molecular mass). Organic compounds in the same homologous series vary by a CH2.

Alkanes (paraffins), alkenes (olefins), Methoxyethane (ethers), and alkynes (acetylenes) form such series in which members differ in mass by 14, 12, and 10 atomic mass units, respectively. For example, the alkane homologous series begins with methane (CH4), ethane (C2H6), propane (C3H8), butane (C4H10), and pentane (C5H12), each member differing from the previous one by a CH2 group (or 14 atomic mass units).

Similarly, there is the alcohol homologous series that starts with methanol (CH4O), ethanol (C2H6O), as primary alcohols, isopropanol (C3H8O) as a simple secondary alcohol, and a simple tertiary alcohol is tert-butanol (C4H10O).

Even while the general formula are the same, they have different structures that can lead the exact same compound to different properties, although they will always present the same chemical properties while as a homologous compound.

Structural isomers are different ways of arranging the same atoms. The more carbons, the more possible ways there will be to arrange the atoms. More:
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