Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions

Which of the following process is not responsible for the presence of electric charge on the sol particles?

Which of the following phenomenon occurs when a chalk stick is dipped in ink?

(i) Adsorption of coloured substance.

(ii) Adsorption of solvent.

(iii) Absorption and adsorption both of solvent.

(iv) Absoprtion of solvent.

Which of the following statements are correct?

(i) A depressant prevents certain type of particle to come to the froth.

(ii) Copper matte contains \[\ce{Cu2S}\] and \[\ce{ZnS}\].

(iii) The solidified copper obtained from reverberatory furnace has blistered appearance due to evolution of \[\ce{SO2}\] during the extraction.

(iv) Zinc can be extracted by self-reduction.

What is the role of flux in metallurgical processes?

Identify the compound Y in the following reaction.

In which of the following molecules carbon atom marked with asterisk (*) is asymmetric?

(a) \[\begin{array}{cc}
\ce{H}\\
|\\
\phantom{.}\ce{C^*}\phantom{}\\
\phantom{}/\phantom{..}|\phantom{..}\backslash\phantom{}\\
\phantom{.}\ce{I}\phantom{...}\ce{Br}\phantom{..}\ce{Cl}
\end{array}\]

(b) \[\begin{array}{cc}
\ce{D}\\
|\\
\phantom{.}\ce{C^*}\phantom{}\\
\phantom{}/\phantom{..}|\phantom{..}\backslash\phantom{}\\
\phantom{.}\ce{I}\phantom{...}\ce{Br}\phantom{..}\ce{Cl}
\end{array}\]

(c) \[\begin{array}{cc}
\ce{H}\\
|\\
\phantom{.}\ce{C^*}\phantom{}\\
\phantom{}/\phantom{..}|\phantom{..}\backslash\phantom{}\\
\phantom{..}\ce{OH}\phantom{..}\ce{C2H5}\phantom{}\ce{CH3}
\end{array}\]

(d) \[\begin{array}{cc}
\ce{H}\\
|\\
\phantom{.}\ce{C^*}\phantom{}\\
\phantom{}/\phantom{..}|\phantom{..}\backslash\phantom{}\\
\phantom{..}\ce{H}\phantom{...}\ce{C2H5}\phantom{}\ce{CH3}
\end{array}\]

Which of the following structures is enantiomeric with the molecule (A) given below:

Which of the following is an example of vic-dihalide?

The position of \[\ce{-Br}\] in the compound in \[\ce{CH3CH = CH(Br)(CH3)2}\] can be classified as ______.

Ethylidene chloride is a/an ______.

Which is the correct IUPAC name for \[\begin{array}{cc}
\ce{CH3 - CH - CH2 - Br}\\
\phantom{}|\phantom{.......}\\
\phantom{}\ce{C2H5}\phantom{....}
\end{array}\]?

What should be the correct IUPAC name for diethylbromomethane?

The reaction of toluene with chlorine in the presence of iron and in the absence of light yields ______.

Which of the carbon atoms present in the molecule given below are asymmetric?

\[\begin{array}{cc}
\phantom{}\ce{HO}\phantom{.....}\ce{OH}\phantom{..}\ce{H}\phantom{.....}\ce{O}\phantom{..}\\
\phantom{..}\backslash\phantom{.....}|\phantom{....}|\phantom{.....}//\phantom{.}\\
\ce{\overset{a}{C} - \overset{b}{C} - \overset{c}{C} - \overset{d}{C}}\\
\phantom{..}//\phantom{.....}|\phantom{....}|\phantom{....}\phantom{.}\backslash\phantom{...}\\
\phantom{}\ce{O}\phantom{......}\ce{H}\phantom{...}\ce{OH}\phantom{...}\ce{H}\phantom{}\\
\end{array}\]

Haloalkanes contain halogen atom (s) attached to the sp³ hybridised carbon atom of an alkyl group. Identify haloalkane from the following compounds.

(i) 2-Bromopentane

(ii) Vinyl chloride (chloroethene)

(iii) 2-chloroacetophenone

(iv) Trichloromethane

Which of the following compounds can be classified as aryl halides?

(i) \[\ce{p-ClC6H4CH2CH(CH3)2}\]

(ii) \[\ce{p-CH3CHCl(C6H4)CH2CH3}\]

(iii) \[\ce{o-BrH2C - C6H4CH(CH3)CH2CH3}\]

(iv) \[\ce{C6H5 - Cl}\]

Which of the products will be major product in the reaction given below? Explain.

\[\ce{CH3CH = CH2 + HI -> \underset{(A)}{CH3CH2CH2I} + \underset{(B)}{CH3CHICH3}}\]

Classify the following compound as a primary, secondary and tertiary halide.

2-Bromo-2-methylpropane

Why can aryl halides not be prepared by reaction of phenol with \[\ce{HCl}\] in the presence of \[\ce{ZnCl2}\]?

Match the items of Column I and Column II.