Chemistry

1. An aqueous solution having \( P^H = 0 \) is

A) acidic   (B) basic      (C) neutral       (D) amphoteric

. The rate constant of a reaction is \( 21 \times 10^{-2} \ mol^{-2} \cdot lit^2 min^{-1} \) The order of the reaction is 

 (A) zero      (B) first       (C) second      (D) third

 For a reaction \( 2SO_2(g) + O_2(g) \rightarrow 2SO_3(g) \) the entropy

(A) increases (B) decreases (C) remain unchanged (D) unpredictable

\( CuSO_4 \) is not stored in aluminum bottle because

 (A) Cu-gets oxidised         (B) Cu-gets reduced

 (C) Al-gets reduced       (D) \( CuSO_4 \) gets decomposed

Carbolic acid is,

 (A) phenol         (B) methanol

(C) formic acid    (D) acetic acid

Acetone \( \xrightarrow{NH_4OH} (X) \xrightarrow{LiAlH_4} (Y) \) in this reaction, the compound (Y) is:

(A) tertiary amine     (B) secondary amine    (C) primary amine    (D) 2 - amine propane.

Chlorobenzene is prepared commercially by:

(A) Dow's process      (B) Deacon's process      (C) Raschig process     (D) Etard's process

8. Which of the following compound gives iodoform test?

(A) propanone      (B) propanal     (C) butanal     (D) butanol

 The colourless liquid (A) reacts with sodium metal at room temperature to produce sodium salt of carboxylic acid and ammonia. Identify liquid compound (A)

 (A) propanamide         (B) propanoic acid

(C) formamide              (D) methyl ethanoate.

The iron pipes carrying drinking water are covered with Zinc to prevent from rusting this process is called...

 (A) allow formation       (B) electroplating          (C) galvanization           (D) electrifying

 Blister copper is,

 (A) ore of Cu          (B) alloy of Cu

(C) pure Cu            (D) Cu containing 1% impurity

You are given a bottle containing a mixture of primary, secondary and tertiary amine. Apply Hoffmann's method to separate each amine in its pure state. 

 Give an example of each of the following reaction.

i) Cannizzaro's reaction

ii) Aldol condensation

iii) Williamson's ether synthesis

iv) Dehydrohalogenation

v) Dehydration of alcohol. 

An organic compound (M) \( C_4H_8O_2 \) undergoes acid hydrolysis to give a carboxylic acid (N) and an alcohol (P). The alcohol (P) is oxidised with \( KMNO_4/H^+ \) to give the carboxylic acid (N)

i) Draw the structural formula of (M), (N) and (P).

ii) What product will you obtain when (M) is reduced in \( LiAlH_4 \)? 

OR

Vinegar is an aqueous solution of acetic acid containing about 5 to 8% by volume in the aqueous solution.

i) Give any three methods of preparation of acetic acid. 

ii) Convert acetic acid into acetic anhydride. 

iii) Mention an important use of vinegar. 

Write down the chemistry of blue-vitriol.

A metal (M) having atomic number 30 is referred as non-typical transition metal and it belongs with the group IIB.

 i) Identify the metal (M) and write its chief ore. 

ii) Why (M) is called non-typical transition metal? 

iii) Write the chemical process occurring in reduction step during the extraction of (M)

 An electrochemical cell is constructed by using Zn electrode and Pb electrode whose standard electrode potential values are -0.76V and -0.13V respectively.

 i) Indicate anode and cathode.  

ii) Write an electro-chemical cell notation. 

 iii) Write down the redox cell reactions.

 iv) Calculate the emf of the cell.

Solubility product principle and common ion effect are simultaneously applied in qualitative salt analysis.

i) Distinguish between solubility product principle and common ion effect. 

ii) Apply solubility product principle and common ion effect in salt analysis of group III B metal ions. 

Or

Define heat of formation. Calculate the heat of formation of acetic acid from the following data:

\( C(s) + O_2(g) \rightarrow CO_2(g), \Delta H = -99 \ Kcal/mol \)

\( H_2(g) + \frac{1}{2}O_2(g) \rightarrow H_2O(l), \Delta H = -68 \ Kcal/mol \)

\( CH_3COOH(l) + 2O_2(g) \rightarrow CO_2(g) + H_2O(l), \Delta H = -208 \ Kcal/mol \)

Represent a regular sequence of chemical reaction of the following sets of organic compounds using suitable reagents, catalysts or conditions with proper reasons. \( CH_3COOH, \) \( CH_3Br \), \( CH_3COOMgBr, \)    \( CH_3MgBr \)

Normality and molarity are the terminologies of volumetric analysis used to express the concentration of solution.

i) Distinguish between molarity and normality. 

 ii) Deduce the normality equation \( S_1V_1 = S_2V_2 \). 

iii) Why is this equation not always used to calculate molarity? 

 iv) Your chemistry teacher added 4gm of sodium hydroxide in a bottle containing 20 CC of 2N \( H_2SO_4 \) and he diluted it up to 1 litre by adding water. Then, he gave you a blue and a red litmus paper.

a) Which litmus paper would you used to test the solution and why?  

b) Calculate the normality of the dilute solution. 

   OR 

In a following given reaction:

\( SO_3 + 3H_2S \rightarrow 3H_2O + 4S \)

a) Express the rate of above reaction in term of reactants and products. 

 b) The concentration of \( H_2S \) decreased by $0.06 mol/litre$ in 2 second. 

 i) Calculate the rate of formation of Sulphur.

 ii) Why is rate of formation of water is not equal to the rate of disappearance of \( SO_3 \)? 

iii) Calculate the rate of disappearance of \( SO_3 \)

 c) Draw an energy profile diagram to illustrate the effect of catalyst on the activation energy hence on rate. 

d) Define energy of activation. 

An alcohol (P) having molecular formula\( C_4H_{10}O \) undergoes Victor-Meyer's test to give blue colour at the end of reaction when added KOH solution.

i) Draw structure formula and write IUPAC name of (P). 

ii) Write down complete chemical reaction for the Victor-Meyer test of (P). 

iii) How would you prepare (P), starting from \( CH_3MgBr \)? 

iv) What product would you obtain when P is oxidised? 

v) Convert propan-1-ol into propan-2-ol. 

Or

i) Give correct chemical reaction for the preparation of chlorobenzene from: 

a) benzene

b) benzene diazonium chloride

ii) Why is haloarene less reactive than haloalkane towards nucleophilic substitution reactions? 

iii) A reaction sequence is given below.

\( C_6H_5Cl \xrightarrow{(P)} C_6H_6 \xrightarrow{(Q)} C_6H_5CH_3 \xrightarrow{CrO_2 / H^+} (R) \xrightarrow{alc. KCN} (S) \)

a) Write down the reagents and conditions for (P) and (Q). 

b) Draw structural formula of (R) and (S). 

 Write short note of pulp and paper industry in Nepal.

b) Give structural formula of monomers and one use of each polymer. 

 i) Polyethene ii) Teflon iii) Bakelite iv) Polystyrene