Basic Principles of Orgainc Chemistry MCQs for NEET — Chemistry Questions with Answers

(d) Benzyl amine, C₆H₅CH₂-N..H₂ is more basic than aniline because benzyl group (C₆H₅CH₂-) is electron donating group due to +I-effect. So, it is able to increase the electron density of N of -NH₂ group. Thus, due to higher electron density, rate of donation of free pair of electron is increased, i.e. basic character is hhigher. Phenyl and nitro group are electron attractive groups, so they are able to decrease the electron density of N of -N..H₂ group. Hence, they are less basic than aniline.

(c) Ethyne (acetylene) have shortest C-C bond length because it has C$\equiv$C bond. The bond length follows the following order

       C$\equiv$C <C=C<C-C

(c) The acidity of halogenated acid increases with increase in electronegativity of the halogen present. So,  the correct order is order is F > Ce >Br

 F${\mathrm{CH}}_2$COOH > Cl${\mathrm{CH}}_2$COOH > Br${\mathrm{CH}}_2$COOH > ${\mathrm{CH}}_3$COOH

Ethanol has a hydroxyl (-OH) group that can participate in hydrogen bonding, whereas dimethyl ether does not have any hydrogen atoms attached to highly electronegative atoms. This intermolecular hydrogen bonding in ethanol results in stronger attractive forces, leading to a higher boiling point.

(c) We know that, inductive effect decreases rapidly with distance. Inductance effect distance depending factor. As the distance of Cl-atom increases the acidic character decreases.

(c) The C-C bond length is maximum for single bond, so butane have largest C-C bond length because it contains carbon-carbon single bond.

The acidic strength of carboxylic acids decreases with an increase in the size of the alkyl group. This is because the larger alkyl groups have a greater electron-releasing or electron-donating effect, which decreases the polarity of the O-H bond, making it less acidic. Therefore, the correct decreasing order of acidic strength is: methanoic acid > ethanoic acid > propanoic acid > butanoic acid.

As the electronegativity of the atom at which -ve charge is present, the stability of the carbanion also increases. The order is

$\mathrm{CH}\equiv {\mathrm{C}}^{-}>{\mathrm{CH}}_2={\mathrm{CH}}^{-}>{\mathrm{CH}}_3^{-}$

Addition of Br₂ in alkene is an example of anti addition. Trans alkene on anti addition give meso compound.

Due to ortho effect, ortho derivative is most acidic. If electron withdrawing group like -NO₂ is present in ring then order of acidity is -o>p->m-