Hydrocarbons MCQs for NEET — Chemistry Questions with Answers

Propadiene, $C_3{H}_4$ molecule contains –

Chlorination of CS₂ gives:

CH$\equiv$CH$\stackrel{{\mathrm{O}}_3/\mathrm{NAOH}}{\to }$X$\stackrel{\mathrm{Zn}/{\mathrm{CH}}_3\mathrm{COOH}}{\to }$Y is: 

Bromination of (E)-2-butenedioic acid gives

"The negative part of the addendum adds on the carbon atom joined to the least number of hydrogen atoms." This statement is called as:

Hydrolysis of propane gives:

Ease of abstraction of hydrogen is greater when attached to:

Which step is chain termination step in the following mechanism?

$$\begin{gathered} \left(\mathrm{i}\right) {\mathrm{Cl}}_2\stackrel{h\nu }{\to }{\mathrm{Cl}}^{\bullet }+{\mathrm{Cl}}^{\bullet } \\ \left(\mathrm{ii}\right) {\mathrm{Cl}}^{\bullet }+ {\mathrm{CH}}_4\to \stackrel{\bullet }{{\mathrm{CH}}_3}+ \mathrm{HCl} \\ \left(\mathrm{iii}\right)\stackrel{\bullet }{\mathrm{C}}{\mathrm{H}}_3+{\mathrm{Cl}}_2\to {\mathrm{CH}}_3\mathrm{Cl}+{\mathrm{Cl}}^{\bullet } \\ \left(\mathrm{iv}\right){\mathrm{Cl}}^{\bullet }+\stackrel{\bullet }{\mathrm{C}}{\mathrm{H}}_3\to {\mathrm{CH}}_3\mathrm{Cl} \end{gathered}$$

Which step is chain propagation step in the following mechanism?

$$\begin{gathered} \left(\mathrm{i}\right) {\mathrm{Cl}}_2\stackrel{h\nu }{\to }{\mathrm{Cl}}^{\bullet }+{\mathrm{Cl}}^{\bullet } \\ \left(\mathrm{ii}\right) {\mathrm{Cl}}^{\bullet }+ {\mathrm{CH}}_4\to \stackrel{\bullet }{{\mathrm{CH}}_3}+ \mathrm{HCl} \\ \left(\mathrm{iii}\right){\mathrm{Cl}}^{\bullet }+{\mathrm{Cl}}^{\bullet }\stackrel{}{\to }{\mathrm{Cl}}_2 \\ \left(\mathrm{iv}\right)\stackrel{\bullet }{{\mathrm{CH}}_3}+ \mathrm{HCl}\to {\mathrm{CH}}_3\mathrm{Cl} \end{gathered}$$

Following is the list of some aromatic compounds. Select the correct sequence of decreasing order of reactivity for electrophilic arpmatic substitution reaction using the answer codes given below:

a. ${\mathrm{C}}_6{\mathrm{H}}_5 - \mathrm{OH}$

b. ${\mathrm{C}}_6{\mathrm{H}}_5 - {\mathrm{CH}}_3$

c. ${\mathrm{C}}_6{\mathrm{H}}_5 - {\mathrm{NO}}_2$

d. ${\mathrm{C}}_6{\mathrm{H}}_5 - \mathrm{CHO}$

Answer codes :