Wurtz Halide Reaction

Q.

Why is Wurtz reaction not preferred for the preparation of alkanes containing odd number of carbon atoms? Illustrate your answer by taking one example.

Q. ${\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{Br}+{\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{Br}\stackrel{\mathrm{Na}/\mathrm{dry}\mathrm{ether}}{\to }\mathrm{The}\mathrm{product}/s\mathrm{formed}\mathrm{are}$

1. ${\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-{\mathrm{CH}}_3$
2. $H_{2}C={\mathrm{CH}}_2$
3. ${\mathrm{CH}}_3-{\mathrm{CH}}_3$
4. All

Q.

Ammonia and hydrogen chloride gases are mixed. Which type of chemical reactions do they give?

Q. Which of the following compounds will undergo racemisation when solution of $KOH$ hydrolyses:

1. (i) and (ii)
2. (ii) and (iv)
3. (iii) and (iv)
4. Only (iv)

Q.

How will you bring about the following conversions ?

(i) Ethanol to but - 1 - yne

(ii) Ethane to bromoethane

(iii) Propene to 1 - nitropropane

(iv) Toluene to benzyl alcohol

(v) Propene to propyne

(vi) Ethanol to ethyl fluoride

(vii) Bromomethane to propanone

(viii) But-1-ene to but-2-ene

(ix) l - chlorobutane to n- octane

(x) Benzene to biphenyl

Q.

How will you convert ethane to ethene?

Q. Write the Nernst equation for the cell reaction in the Daniel cell. How will the $E_{\text{cell}}$ be affected when the concentration of $Z{n}^{2+}$ ions is increased?

Q. Methane cannot be prepared by :

1. Wurtz reaction
2. Soda Lime process
3. Kolbe's reaction
4. Sabatier-senderens reaction

Q. To prepare a pure sample of n-hexane using sodium metal as one reactant, the other reactant or reactants will be:

1. ethyl chloride and n-butyl chloride
2. n-propyl bromide
3. ethyl bromide and n-butyl bromide
4. methyl bromide and n-pentyl bromide

Q. Which one of the following alkylbromide may be used to prepare 2, 3-dimethylbutane by wurtz reaction?

1. n-propyl bromide
2. isopropyl bromide
3. isobutyl bromide
4. s-butyl bromide

Q.

Hydrocarbon (A) reacts with bromine by substitution to form an alkyl bromide which by Wurtz reaction is converted to a gaseous hydrocarbon containing less than four carbon atoms. (A) is:

1. $C{H}_3-C{H}_3$
   
2. $C{H}_2=C{H}_2$
   
3. $CH\equiv CH$
   
4. $C{H}_4$
   

Q. One gas bleaches the colour of flowers by reduction while the other by oxidation

1. $CO$ and $C{l}_2$
2. $S{O}_2$ and $C{l}_2$
3. $H_{2}S$ and $B{r}_2$
4. $N{H}_3$ and $S{O}_2$

Q. $RMgX+C{O}_2\underset{\text{ether}}{\overset{\text{dry}}{\to }}Y\stackrel{H_3{O}^{+}}{\to }RCOOH$
What is $Y$ in the above reaction?

Q.

Pure methane can be produced by -

1. Wurtz reaction

2. Kolbe’s electrolytic method

3. Soda-lime decarboxylation

4. Reduction with ${\mathrm{H}}_2$

Q. Of the four oxyacids of chlorine, the strongest oxidizing agent in dilute aqueous solution is

1. 
2. 
3. 
4. 

Q. Wurtz reaction using bromoethane yields:

1. 2-bromobutane
2. n-butane
3. isobutane
4. ethane

Q. When isobutyl magnesium bromide in dry ether is treated with absolute ethyl alcohol, the products formed are

1. $C{H}_3-CH-C{H}_{2}OHandC{H}_{3}C{H}_{2}MgBr|C{H}_3$
2. $C{H}_3-CH-C{H}_2-C{H}_2-C{H}_{3}andMg\left(OH\right)Br|C{H}_3$
3. $C{H}_3-CH-C{H}_{3}andC{H}_3-C{H}_{2}OMgBr|C{H}_3$
4. $C{H}_3-CH-C{H}_3,C{H}_2=C{H}_{2}andMg\left(OH\right)Br|C{H}_3$

Q. A solution of sulphur dioxide in water reacts with $H_{2}S$precipitating sulphur. Here sulphur dioxide acts as

1. A catalyst
2. An acid
3. As oxidising agent
4. A reducing agent

Q.

How will you distinguish between ammonium hydroxide and sodium hydroxide using copper sulfate solution?

Q. The product formed in the reaction is:

1. $\left(BrC{H}_2{)}_{3}CC{H}_{2}C{H}_{2}C\right(C{H}_{2}Br{)}_3$
2. 
3. 
4. 

Q.

When 20ml of methane and 20ml of oxygen are exploded together and the reaction mixture is cooled to laboratory temperature. The resulting volume of the mixture

Q. What is the meaning of Mechanical strength

Q. Which of the following compounds will give a significant amount of meta-product during mono - nitration reaction?

1. 
2. 
3. 
4. 

Q. 21. Can a solution of 1M cuso4 stored in a Nickel metal vessel E^° Ni2+/Ni=-0.25V & E^° cu2+/Cu=+0.34V

Q. Propene is treated with $C{l}_2/CC{l}_4$. The product formed is

1. 
2. 
3. 
4. 

Q. Ethyl iodide and $n-$propyl iodide are allowed to undergo Wurtz reaction. The alkane which will not be obtained in this reaction is:

1. Butane
2. Propane
3. Pentane
4. Hexane

Q.

A ______ (black/white) precipitate of ______ ___(barium sulphate/ barium bisulphate) is formed when barium chloride is treated with sulphuric acid.

Q.

Define the terms “oxidising agent” and “reducing agent”.

Q.

State which of the following chemical reactions will take place or not, giving the suitable reason for each.

1. $\mathbf{Zn}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{CuSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{}{\mathbf{ZnSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{Cu}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$
2. $\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{ZnSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{}{\mathbf{FeSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{Zn}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$
3. $\mathbf{Zn}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{FeSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{}{\mathbf{ZnSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$

Q.

An example of deliquescent salt is-

1. CaCl₂

2. CaSO₄

3. CuSO₄

4. NaCl