Addition Reactions

Q. 2, 3-Dimethyl-2-butene can be prepared by heating which of the following compounds with a strong acid?

1. $(C{H}_3{)}_{2}C=CH-C{H}_2-C{H}_3$
2. $(C{H}_3{)}_{2}CH-C{H}_2-CH=C{H}_2$
3. 
4. $(C{H}_3{)}_{3}C-CH=C{H}_2$

Q. How many stereoisomers does this molecule have?
$C{H}_{3}CH=CHC{H}_{2}CHBrC{H}_3$

1. $8$
2. $2$
3. $4$
4. $6$

Q.

How is BUNA – S prepared? Write any 2 uses and properties of it.

Q.

Give preparation and uses of D.D.T.

Q. An alkene "A" on reaction with $O_3$ and $Zn-H_{2}O$ gives propanone and ethanal in equimolar ratio.
Addition of $HCl$ to alkene $A$ gives $B$ as the major product. The structure of product $B$ is:

1. 
2. 
   
3. 
   
4. 
   

Q.

Draw the resonance structures for the following compounds. Show the electron shift using curved-arrow notation.

(a) C₆H₅OH (b) C₆H₅NO₂ (c) CH₃CH = CH – CHO

(d) C₆H₅CHO (e) (f)

Q.

Define the Kharasch effect.

Q. Why melting point of trans is greater than cis ?

Q. When 100g of ethylene polymerises entirely to polyethene , the weight of polyethene formed as per the equation nCH2=CH2 gives (CH2 -CH2)n

Q.

Write down the products of ozonolysis of 1, 2-dimethylbenzene (o-xylene). How does the result support Kekulé structure for benzene?

Q. Which of the following compound is most likely to follow E1cB mechanism when treated with $C_2{H}_{5}ONa$ in ethanol?

1. 
2. 
3. 
4. 

Q. The addition of HBr to an alkene in the presence of peroxide is an example of :

1. electrophilic substitution reaction
2. acid catalysed reaction
3. free radical addition reaction
4. nucleophilic addition reaction

Q. The correct order of reactivity of addition of hydrogen halides with alkene is:

1. HBr>HF>HCl>HI
2. HCl>HBr>HI>HF
3. HI>HBr>HCl>HF
4. HF>HBr>HCl>HI

Q. The correct structure of the product A formed in the reaction

1. 
2. 
3. 
4. 

Q.

The major product [R] in the following sequence of reactions is:

1. 

2. 

3. 

4. 

Q. Which is better oxidising agent out of KMnO₄ and K₂Cr₂O₇ ?

Q.

What is hydrogenation? What is its industrial application?

Q. Which one has the highest heat of hydrogenation?
III
III

1. II
2. I
3. III
4. None of the above

Q.

Which alkene gives only acetone on ozonolysis?

Q.

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Dipole-dipole interactions are only non-covalent interactions, resulting in hydrogen bond formation.
Reason R: Fluorine is the most electronegative element and hydrogen bonds in HF are symmetrical.
In the light of the above statements, choose the most appropriate answer from the options given below:

(a) A is false but R is true

(b) Both A and R are true and R is the correct explanation of A

(c) A is true but R is false

(d) Both A and R are true and R is not the correct explanation of A

Q.

Name the reaction which is commonly used in the conversion of vegetable oils to fats. Explain the reaction involved in detail.

Q. The correct order of thermal stability of hydrogen halides (H – X) is

1. HI > HBr > HCl > HF
2. HF > HCl > HBr > HI
3. HCl < HF < HBr < HI
4. Hi > HCl < HF < HBr

Q.

${\mathrm{CH}}_3\mathrm{CN}+2{\mathrm{H}}_2\stackrel{\mathrm{Na}\left(\mathrm{Hg}\right)/{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}}{\to }$?

Q.

C₆H₅ONa + C₂H₅Cl $\to$_________________________________

Q. Which of the following is the correct order for the reactivity of alkenes towards electrophilic addition?

1. Ethene > Propene
2. $C{H}_2=CH-OC{H}_3>C{H}_2=CH-C{H}_2-OH$
3. $C{H}_2=CHN{O}_2<C{H}_2=C(N{O}_2{)}_2$
4. $C{H}_2=CH-N{O}_2>C{H}_2=CH-OC{H}_3$

Q.

The major product obtained from E2 – elimination of 3-Bromo-2-fluoropentane is:

1. 

2. 

3. 

4. 

Q. When hydrochloric acid gas is treated with propene in presence of benzoyl peroxide, it gives

Q. Free radical chlorination of butane gives 2-chlorobutane and 1-chlorobutane. 2-chlorobutane formed is

1. $(+)$ isomer
2. $(-)$ isomer

3. $(\pm )$ isomer

4. Meso

Q. In presence of peroxide, hydrogen chloride and hydrogen iodide do not give anti - Markownikoff's addition to alkenes because

1. All the steps are exothermic in both the cases
2. Both are highly ionic
3. One is oxidising and other is reducing
4. One of the steps is endothermic in both the cases

Q.

What is the order of melting point of haloarene when halogen is placed at ortho mera and para