Ncert Solutions Chemistry Class 12th

The 'X' in reaction is 3-hydroxybutanal. It is an aldol reaction. Complete reaction is an follows:

Ethyl benzoate can be prepared by heating benzoic acid with ethyl alcohol in presence of dry HC1 or conc. The reaction is called as esterification reaction.

The carbon next to an alkene is known as allylic carbon and halogen attached to allylic carbon is known as allylic halogen.

 

Boiling points of aldehydes are higher than hydrocarbons. It is due to weak molecular association.

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The colour changes due to change in pH not due to its reaction with water.

Each of the element in group III  to VIIIB  can show the maximum oxidation state equal to its group number.

Mn is in group seven shows a maximum oxidation state of +7 in KMnO₄

Please find the solution below:

In the metallurgy of aluminium, purified Al₂O₃ is mixed with Na₃AIF₆ or CaF₂ which lowers the melting point of the mixture and brings conductivity.