Question

What isn1°,2°,3° and 4° of hydrocarbons

Answer 1

1 degree or primary carbon atom are those carbon atom in which only one valency of carbon atom is satisfied by another carbon atom and other are satisfied by any different element e.g. CH3-CH3 in ethane both carbon atom are primary carbon atom.
2-degree or secondary carbon atom are those carbon atom in which two valencies of carbon atom is satisfied by other 2 carbon atoms and other valencies are satisfied by any different element.
e.g. CH3-CH2-CH3 in propane middle carbon atom is secondary carbon atom in this example middle carbon atom is attached ony two carbons.
similarly 3-degree or tertiary carbon atom are those carbon atom in which three valencies of carbon atom is satisfied by other 3 carbon atoms and other valencies are satisfied by any different element
e.g. (CH3)3-CH in 2-methylpropane the CH carbon atom is tertiary carbon atom.
4-degree or quaternary carbon atom are those carbon atom in which all 4 valencies of carbon atom is satisfied by other 4 carbon atoms. e.g. (CH3)4-C in 2,2-dimethylpropane in this that C carbon atom is quaternary carbon atom