Chemistry Model Question Class-12

SET- 1 

Group -A 

Multiple choice Questions 11×1 = 11

1. The pH of the aqueous solution of a 0.1 M solution of a weak 1% ionisable monoprotic acid is 

  1. 2
  2. 3
  3. 4
  4. 5

2. Which of the following behaves as Bronsted acid and Bronsted base?

  1. $HCO_3^-$
  2. $OH^-$ 
  3. $NH_2^-$ 
  4. $Na_2CO_3$

3. 5 mL of 10N HCl is taken in a 250 mL volumetric flask and water is added up to the mark. The  normality of the resulting solution is a. 0.2N  

  1. 0.2N  
  2. 1.5N  
  3. 2N  
  4. 4N  

4. Zn reacts with dil. acid to give hydrogen gas, but Cu can't. Which of the following should be the reduction potential of Zn, $H_2$ and Cu respectively?

  1. -0.72, 0, +0.34  
  2. L+0.72, 0, -0.34
  3. -0.72, 0, -0.34  
  4.  +0.72, 0, +0.34

5. The reagent to prepare chloroalkane from alcohol is  

  1. Conc. HCl  
  2. $PCl_5$
  3. $PCl_3$ 
  4. $SOCL_2$

6. Tear gas is  

  1. Chloretone  
  2. Chloropicrin  
  3. Benzyl chloride  
  4. Phenol  

7. Ether on hydrolysis gives  

  1.  Acid  
  2. Alcohol  
  3. Ester  
  4. Ketones  

8. Iodoform test is given by 

  1. Formaldehyde  
  2. Propanal  
  3. Propan-1 ol  
  4. 2-Propanone

9. The β-decay of 11Na24 produces an isotope of

  1. Na  
  2. Al  
  3. Mg  
  4. Ne

10. The geometry of $Cu(NH_3)_4]SO_4$ is  

  1. Square planar  
  2. Octahedral  
  3. Tetrahedral  
  4. Pyramidal

11. Mohr's salt is a 

  1. Acidic salt  
  2. Basic salt  
  3.  Neutral salt  
  4. Double salt  

Group - B 

Short Answer Questions 8×5 = 40

1. Write the difference between order and molecularity. A first order reaction was started with a  decimolar solution of the reactant. After 500 s its concentration was found to be 0.01M. What  time would it take to complete half of the reaction? [2+3] 


A solution of known concentration is called a standard solution. [1+1+1+2]  

  1. Are all standard solutions primary standard solutions or not? Give reasons.
  2. Give any two examples of primary standard substances.  
  3. What is the importance of calculating normality factor of solution during titration?  
  4. What volumes of N/2 and N/10 HCl must be mixed to give 2 Litres of N/5 HCl? 

2. The figure shows the octahedral distortion of the d – orbital in the presence of ligands.


  1. Why does octahedral distortion occur in the presence of ligands? Explain on the basis of CFT.  
  2. Why do$t_{2g}$ – orbitals have lower energy than $e_g$ – orbitals in the octahedral complex?  
  3. On the basis of the given distortion how can you explain that $Cu(H_2O)_6]^{2+}$ is a blue coloured  complex?  
  4. Fill up the electrons in $t_{2g}$ – set and eg – set of the central metal of $[Fe(CN)_6]^{4-}$ion.  
  5. Is the $[CoF_6]^{3-}$complex ion expected to be high or low spin complex? Give a reason.

3. The brown layer appears on iron metal on long term exposure to the air which causes degradation  on the quality of iron.  

  1. Give the molecular formula of the brown layer on iron. 
  2. Discuss in brief about the electronic theory about rusting on iron. 
  3. Mention suitable methods to save iron from rusting.  

4. Chemical drugs are used for various reasons in daily life.  

  1. The structure of the drug is given below. Identify the drug and write its main use.  
  2. Write an example of each: i. Herbicide ii. Fungicide  
  3. What is the difference between OPC and PPC cement? [1+1+1+1+1] 

5. Define the terms homopolymer and copolymer. Explain in brief about radioactivity with examples. Show its use in the medical field. [1+1+1+1+1] 

6. The following are the different types of amines; $CH_3CH_2NH_2, NH(CH_3)_2, N(CH_3)_3$ 

  1. Arrange the above amines in the increasing order of base strength in aq. medium and explain  the reason briefly.  
  2. How would you distinguish the above given amines?[2+3] 


 Aromatic –OH group behave slightly different than aliphatic alcohols. [1+1+1+2] 

  1. Identify the compound A 
  2. Write the laboratory test of phenol.
  3. Starting from phenol, how would you prepare p – hydroxyazobenzene?  
  4. Convert phenol to benzaldehyde  

7. In large scale production of alcohol fermentation is carried out on either sugar or starch using  yeast. [3+1+1]  

  1. Give a brief explanation of this process using sugar to obtain alcohol with a suitable reaction.  
  2. What is the use of (NH4)2SO4 in this process?  
  3. Name the optical isomers involved in the process.

8. Study the following data for the thermodynamic process $H_2O_{(i)} \rightarrow H_2O_{(s)}$ at different  temperatures at 1 atm pressure. [1+1+2+1]  




Entropy change in J/Kmol 

Entropy of system 

Entropy of surrounding 









  1. Calculate the total entropy of the universe at given condition 3.  
  2. Can we predict the spontaneity of the given reaction at 0℃?  
  3. Calculate the equilibrium constant for the fusion of ice at 1℃. What is the effect of temperature  for the entropy change of reaction? 

Group - C

Long Answer Questions 3×8 = 24 

1. Define a buffer solution. Give one example each of acid buffer and basic buffer.  Mention the condition for a solution to produce precipitation. What amount of $Zn(OH)_2$ will be  precipitated out at 25℃ if 100 mL of 0.22 g NaOH is added to 1 L of a saturated solution of  $Zn(OH)_2$? If precipitate is obtained in reaction, why? [Solubility product of $Zn(OH)_2$ at 25℃ is 1.8  x $10^{-14}$]. [1+2+1+3+1]  


The standard electrode potential for the following electrode reaction at standard state is given 

  1. Define standard electrode potential. [1]  
  2. Why single electrode potential cannot be calculated? [1]  
  3. Write the cell notation indicating anode and cathode. [1]  
  4. With 1M solution of ions at 25℃ and 1 atm pressure, what will be the cell potential? [1]  
  5. Calculate the free energy change in the reaction. [2]  
  6. Can we store Ag$NO_3$ solution in a copper vessel? Give a reason. [2]  

2. The compound A having molecular formula $C_3H_8O$, when treated with dil. $H_2S)_4$ forms compounds  B and C. The compound B gives positive iodoform test. When compound C is passed over heated  Cu at 300℃, then compound D is formed. The compound D on reacting with phenol gives  thermosetting plastic E. identify A, B, C, D, and E with pertinent reactions. Also give the molecular  formula of functional isomer of A. convert this isomer to compound A with suitable reagents. [5+1  +2]  


Aldehyde and ketones are called carbonyl compounds. In ketones, the carbonyl group is bonded to  two alkyl and aryl groups, while in aldehyde, the carbonyl group is bonded to one H except in  formaldehyde. 

  1. Give the chemical test reaction to distinguish aliphatic aldehydes and ketones. [2] 
  2. The compound A on ozonolysis produces acetaldehyde and formaldehyde. Identify the compound A. [1]  
  3. Among acetaldehyde and formaldehyde, which one gives aldol condensation reaction? Write  a reaction. [2]  
  4. Write a reaction to convert benzene into acetophenone. [1]  
  5. How would you obtain urotropine from aldehyde? Write the structure and use of urotropine.  [2]  

3. Write the principle and reaction only for the Lab preparation of $CHCL_3$. Write the reaction of $CHCL_3$  with a. Ag b. Conc. NH$O_3$ c. Acetone d. Zn/$H_2$O e. Aniline [3+5]  

SET -2

Group - A

A Multiple Choice Questions 11×1 = 11

1. When 100 mL of decinormal HCl solution reacts with 1 g of CaC$O_3$, normality of the resulting  solution is  

  1. 1N  
  2. 0.1N  
  3. 0.75N  
  4. 0.99N  

2. Which will make the basic buffer?  

  1. 100 mL of 0.1 M C$H_3$COOH + 100 mL of 0.1 M NaOH  
  2. 100 mL of 0.1 M C$H_3$COOH + 100 mL of 0.1 M N$H_4$OH  
  3. 100 mL of 0.1 M HCl + 100 mL of 0.1 M NaOH  
  4. 100 mL of 0.1 M HCl + 100 mL of 0.1 M N$H_4$OH  

3. 50% of the zero order reaction was completed in 20 minutes. When was 87.5% of the reaction  completed? 

  1. 70 min  
  2.  60 min  
  3. 35 min  
  4. 20 min 

4. Standard reduction potential for $Zn^{2+}$/Zn and $H^+/H_2$are -0.76 V and 0.00 V respectively. Which of  the following has the highest reducing capacity? 

  1. $Zn^{2+}$ 
  2. Zn  
  3.  $H^+$ 
  4. $H_2$

5. Maximum number of unpaired electrons is present in  

  1. $Cr^{3+}$
  2. $Sc^{3+}$
  3. $Ti^{3+}$ 
  4. $Fe^{2+}$ 

6. Zinc sulphate is used in medicine as a  

  1. Tranquilizer  
  2. Antiseptic  
  3. Styptic  
  4. Analgesic  

7. Radioiodine (I-131) therapy is used in treatment of  

  1. Thyroid cancer  
  2. Prostate cancer  
  3. Breast cancer  
  4. Blood cancer  

8. Which of the following products is obtained when nitrobenzene is electrolytically reduced? 

  1. p aminophenol  
  2. azobenzene  
  3. azoxybenzene  
  4. hydrazobenzene  

9. Ethers are  

  1. Lewis acid  
  2. Lewis base  
  3. Bronsted base  
  4. Polar solvent  

10. The reaction of HCN with aldehyde to give cyanohydrin is  

  1.  Electrophilic addition  
  2. Nucleophilic addition;  
  3.  Electrophilic substitution  
  4. Nucleophilic substitution  

11. Victor Grignard received Nobel Prize in chemistry in  

  1. 1900 A.D.  
  2. 1908 A.D.  
  3. 1912 A.D.  
  4. 1916 A.D. 

Group -B 

Short Answer Questions  8 x 5 = 40 

1. How is free energy change of a reaction related with enthalpy change and entropy change? Heat  of formation of carbon dioxide, water and glucose are =395 $KJmol^{-1}$, -269 $KJmol^{-1}$ and -1169  $KJmol^{-1}$respectively. Calculate heat of combustion of benzene. [2+3]  OR  

For a reaction:  P + Q → Z  

Following data were obtained  




Rate Ms-1 



5.07 x 10-5



5.07 x 10-5



1.43 x 10-4


  1. Order of reaction with respect to [P].  
  2. Write the rate law expression for this reaction.  
  3. Show the half-life period of first order reaction is independent of initial concentration of  reactant. [2+1+2]  

2. State Ostwald’s dilution law. Why is it not applicable for strong electrolytes? What will be the  resultant pH, when 200 ml of an aq. Solution of HCI (pH=2) is mixed with 300ml of an aq. Solution  of NaOH (pH=12). [1+1+3]  

3. Explain the general steps along with relevant reactions involved in the extraction of pure iron from  iron pyrite. Write a reaction to convert iron to green vitriol. [4+1]  

4. $K_4[Fe(CN)_6]^{4-}$is a green complex formed by iron.  

  1. Why does iron form coloured complex?  
  2. Define complex ions. Identify the ligand in the above example and write an example of one more  ligand.  
  3. Define coordination number. What is the coordination number and charge of iron in complex  $K_4[Fe(CN)_6]^{3-}$

5. $CH_3CH_2CH_2Br+KOH$  → (aq) B + KBr  

  1. Identify the compound B.  
  2. Which substitution reaction mechanism occurs in the above reaction and why?  
  3. What is the product formed when alc. KOH solution is used instead of aq. KOH in the above  reaction?  


  1. Draw the resonating structure of chlorobenzene and explain why it is o,p – directing towards  electrophilic substitution reaction.  
  2. Nucleophilic substitution reaction is difficult in chlorobenzene. Explain.  
  3. How would you obtain chlorobenzene from benzene? Give a reaction. 
  4. What happens when chlorobenzene is heated with chloral? Write reaction  

6. A chemistry researcher has given three compounds. He has to identify the compounds by doing some  tests in the lab using a common reagent. Some of the features of these compounds have given in  the table below:  



Gives alcohol and nitrogen 

Gives water soluble trialkyl ammonium nitrite salt 

Yellow oily liquid and insoluble in mineral acids 

Identify the common reagent used and show general reactions for these compounds. What would  happen when compound C is treated with di-ethyl oxalate? Among A and B, which one has high  solubility and why? [3+1+1]  

7. Willard Libby was awarded the Nobel Prize for developing 14C dating.  

  1. Write the principle of dating.  
  2. Mention any two radioisotopes used in the medical field. [1+1] Define pulp. Explain  chemical pulping process. [1+2]  

8. What are primary raw materials for cement? Mention two major considerations while selecting raw  material for cement. [1+2]  

  1. Write a characteristic of an ideal drug. Name two antipyretic drugs. [1+1] 

Group - C 

Long Answer Questions  3 x 8 = 24

1. Elemental analysis of a 3° haloalkane (A) with a molecular mass 120.5 amu showed the presence of  59.75% carbon and 10.79% hydrogen. The compound on treatment with alcohol. KOH gave a  compound B, which on ozonolysis gave a single compound C. The compound C was found to give  positive 2,4-DNP test but negative silver mirror test . Identify A, B and C and write the relevant  reactions. [2+3]  

A compound X and Y reacts with Conc. $H_2SO_4$ to give a compound Z, which is widely used in acid  base titration .Compound X is widely used in manufacture of electrical appliances. Compound Y is  prepared by heating phthalic acid. 

  1. Show the reaction of X with Y  
  2. Show the reaction of X with formaldehyde.  
  3. What happens when X is treated with $CO_2$? [1+1+1]  


An organic liquid (A) reacts with sodium nitrite and dilute hydrochloric acid in an ice bath to give  compound B which warms with cuprous chloride in dil. HCl gives compound C. When C is  heated with NaOH at about 350° C under high pressure followed by acidification D is formed. D reacts with aqueous bromine to give white ppt E which on heating with Zn dust gives  1,3,5 tribromobenzene .Identify A, B, C, D and E with necessary chemical reactions . [5]  

  1. Methanoic acid gives Tollens test though it is an acid not an aldehyde. Explain with reaction. [2+1] 

2. The figure given below shows a redox couple containing $Zn^{++}Zn$ and SHE. It is being used to  determine the reduction potential of zinc electrodes.  

  1. What is standard electrode potential? Write factors affecting standard electrode potential.
  2. What is SHE? Why is it used as a cathode in galvanic cells?  
  3. Write cell notation for the given cell  
  4. Name any one other electrode that can be used instead of SHE for the purpose. Write its  advantage over SHE.  
  5. The voltmeter shows the reading 0.76V. Interpret this value in terms of cell potential of the  galvanic cell and standard potential reduction of zinc electrode. [2+2+1+2+1]  

3. The substation reaction is defined as a reaction in which the functional group of one compound is  substituted by another group or it is a reaction which involves the replacement of one atom or a  molecule of a compound with another atom or molecule. There are different types of substitution  reactions,  

  1. What is nucleophilic substitution reaction? What are SN1 and SN2 reactions?  
  2. Why is nucleophilic substitution difficult in halobenzene as compared to haloalkane?  
  3. What is Williamson synthesis? Give an example.  
  4. What happens when n-propyl chloride is treated with alc. solution of AgCN? [1+2+2+2+1] 

SET- 3

Group - A

Multiple Choice Questions 11×1= 11

1. The Solubility product of chalk is 9.3×10-8. What is the solubility in grams per litre? 

  1. 3.04 x $10^{-1}$ 
  2. 3.04 x $10^{-2}$  
  3. 3.04 x $10^{-3}$  
  4. 3.04 x $10^{-4}$

2. What happens when a lead storage battery is discharged?  

  1. $SO_2$ is evolved  
  2. Pb$SO_4$ is consumed  
  3. Lead is formed  
  4. $H_2SO_4$ is consumed 

3. Which of the following concentration terms is temperature independent?

  1. Molarity  
  2. Mole fraction  
  3.  g/L  
  4. Normality  

4. The rate of reaction doesn't depend on  

  1. Concentration of reactant  
  2. Suitable catalyst  
  3. Temperature  
  4. Concentration of product  

5. Most ionic bond with carbon is of  

  1. K  
  2. Na  
  3. Li  
  4. Mg  

6. Mixture of chlorobenzene and aniline can be separated by  

  1. Ether  
  2. Dil. HCl  
  3. NaOH  
  4. Alcohol  

7. Which of the following nitroalkane cannot exist in aci form  

  1. $CH_3NO_2$
  2. 1° nitroalkane  
  3. 2° nitroalkane  
  4. 3° nitroalkane  

8. The sour test in lemon is due to  

  1. Oxalic acid  
  2. Citric acid  
  3. Tartaric acid  
  4. HCl  

9. Which of the following ore is concentrated by the froth-floatation method?  

  1. Hematite  
  2. Siderite  
  3. Galena  
  4. Malachite  

10. Which cannot act as ligands in transition metals?  

  1. CO  
  2. $CO_2$
  3. $NH_3$ 
  4. $H_2O$  

11. Removal of which of the following leads to higher fibre-fibre bonding strength in paper? 

  1. Softwood 
  2. Hardwood  
  3. Lignin 
  4. Pulp  

Group -B 

Short Answer Questions 8×5= 40

1. What do you mean by batteries? Differentiate between primary and secondary standard batteries.  Write down the reaction taking place at the cathode and anode during discharging of lead storage  battery. [1+2+2]  


  1. Derive the relation K = $\frac{2.303}{t} log\frac{a}{a-x}$
  2. A first order reaction is 50% completed in 5 hours. How many time would it take for 90%  completion? [3+2]  

2. Explain the method of extraction of mercury from cinnabar (HgS). [5]  

3. The figure shows the octahedral distortion of the d-block orbital in the presence of ligands.

  1. What are ligands? Why do strong field ligands give rise to the formation of low spin complexes? 
  2. Among fig A and B, which one is weak ligand field, why?  
  3. Most of the ions of transition metals are colored, why?  
  4. The compounds of $V^{5+}$ are colorless while that of $V^{3+}$ are colored, why? [2+1+1+1]  

4. Aspirin is a pharmacodynamics drug and used as antipyretic and analgesics. Its generic name is  acetylsalicylic acid and can be prepared from phenol.  

  1. What do you mean by antipyretics and analgesics?  
  2. Suggest a suitable chemical reagent, A and B in above reaction condition.  
  3. Write any two major differences between OPC and PPC cement? [1+2+2]  

5. Mention two factors on which quality of paper depends. Write a use of paper. [2+1] Why 14C  is radioactive but 12C is not? Write one disadvantage of radioactivity. [1+1]  

6. In the following reaction series, compound A is an aromatic compound which reacts with  chloral in the presence of conc. $H_2SO_4$ to form an important insecticide which is used to control  malaria and typhus. Identify A, B, C, D and E.


An aromatic compound P in which one chlorine atom is substituted at a benzene ring. When the  compound P is treated with an acid chloride containing two carbon atoms in the presence of  anhydrous $AICI_3$gives R

  1. Identify P and R.  
  2. Reaction of aq. NaOH on the compound P is more difficult than with chloroethane. Justify with  suitable examples.  
  3. How do you get compound P from benzene diazonium chloride? [1+1+2+1]

7. The given table shows the compounds and their molecular formula. How can you convert P to Q,  where Q is the compound in which two methyl groups are substituted at adjacent carbons? How  is P obtained from T, where T is secondary alcohol? Write the reaction involved in the conversion  of P into R and S.  


Molecular formula 






8. What is Gibb's free energy? How spontaneity of a reaction can be predicted from Gibb's-Helmholtz equation for exothermic and endothermic reaction at different temperatures?

Group -C 

Long Answer Questions  3 x 8 = 24

1. The compound A ($C_3H_6O_2$) on hydrolysis, two compounds B and C are formed, the compound B on  heating in presence of $P_2O_5$, acetic anhydride is obtained. The compound C on oxidation with  strong oxidizing agent gives the compound D. Compound D shows a positive Tollens test. Identify  A, B, C, D. What happens when compound D is treated with sublime? [1+1+1+1+1]

Write an example of each of the followings: (3)

  1. Carbylamine test 
  2. Hoffmann’s degradation reaction 
  3. Diazotization reaction 


  1. A primary alcohol with the molecular weight 46 is boiled with NaOH and Iodine. When the  same alcohol is heated with the ethanoic acid in the presence of Conc. H2SO4, one of the derivatives  of carboxylic acid is obtained. Write the reactions involved in both conditions. What would be  the product obtained when the same alcohol is heated with Conc. H2SO4? How would you  distinguish the above alcohol from methanol? [1+1+1+1]  
  2. An Aromatic compound known as oil of mirbane (Nitro benzene) is prepared from benzene. 
  1. What product would you obtain when the compound is electrolyzed in an acidic medium?  
  2. What happens when the compound is treated with a nitrating mixture above 60 ℃.
  3. Give complete reaction for the conversion of the compound to yellow dye. [1+1+2]  

2. State Ostwald's dilution law. [1]  

At 25 ℃, the dissociation constant of $CH_3COOH$ is 1.8 x $10^{-5}$. For the 2M $CH_3COOH$ solution, calculate the degree of ionization and pH of the solution. [2]  

  1. Show your familiarity with the Bronsted-Lowry concept of acid and base. [2]  
  2. Describe any one important application of solubility product principle. [1]  
  3. Explain the selection of suitable indicator used in the titration of [2]  
  1. Strong acid and strong base
  2. Strong acid and weak base 


  1. Heat of combustion of benzene is -3280 $KJmol^{-1}$. Heat of formation of $CO_2$ and $H_2O$ are -395  $KJmol^{-2}$ and -286 $KJmol^{-2}$ respectively. Calculate the heat of formation of benzene. [3]  
  2. Answer the following question related to the given figure of $H_2- O_2$ fuel cell. [1+2+2] 

  1. Identify A, B and C
  2. Write the anodic, cathodic and overall reaction involved in the cell.  
  3. Write the advantages and limitations of the fuel cell.  

3. Two isomeric compounds A and B have the same molecular formula $C_3H_5N.$ Predict the structure of and B on the basis of following information. [5] 

  1. A and B does not react with $HNO_2$.  
  2. On refluxing with dil. HCI, A gives C and B gives D being the monobasic acids.  
  3. Molecular mass of D is 74.  

Arrange the following compounds in ascending order of their basicity. Explain this order in detail.  [3]  

  1. Trimethylamine 
  2. Aniline 
  3. ammonia  

SET- 4

Group - A 

Multiple Choice Questions: 11×1 = 11  

1. Number of moles of solute dissolved in 1000 gm of water is  

  1. Molality  
  2. Molarity  
  3. Mole fraction  
  4. % (W/V)  

2. Enthalpy of a compound is equal to its  

  1. Heat of combustion  
  2. Heat of formation  
  3. Heat of solution  
  4. Heat of dilution  

3. The atomic number is changed by which type of radioactive decay? 

  1. β  
  2. α  
  3. γ  
  4. All of the above  

4. Which of the following compounds is known as Schweitzer’s reagent? 

  1. $CuSO_45H_2O$  
  2. $CaSO_4$
  3. $[Cu(NH_3)_4]SO_4$
  4. Anhydrous Copper  

5. Which of the following is not true regarding crystal field theory?  

  1. Action between metal and ligand is electrostatic  
  2.  ligand are treated as point charge  
  3. There is no orbital interaction between ligand and metal  
  4. Hybridization explain the shape of the complexes  

6. Ether is always purified before distillation because,  

  1. It is highly poisonous in nature  
  2. It forms poisonous phosgene gas  
  3.  It is converted into explosive peroxide  
  4.  All of above  

7. Which of the following is an organometallic compound?  

  1. $CH_3ONa$ 
  2. $CH_3SNa$ 
  3. $CH_3MgCI$  
  4.  All of the above  

8. Solubility of a salt M2X3 is "x " mol L-1.The solubility product of the salt will be

  1.  $x^5$ 
  2. $16x^2$ 
  3. $96x^5$
  4. $108x^5$

9. Alcoholysis of acid anhydride gives  

  1. Carboxylic acid and ester  
  2. Ester and alcohol  
  3. Carboxylic acid and alcohol 
  4. Only ester  

10. An organic compound 'A' reacts with nitrous acid to form N - Methyl - N - nitroso ethanamine. A  can be obtained by the reduction of …..  

  1. Propanenitrile  
  2. Methyl Isocyanate  
  3. Ethyl Isocyanide  
  4. Propyl Isocyanide  

11. Given E0 Cr /Cr+3 = 0.072 V, E0 Fe+2/Fe = 0.42 V. The Standard cell potential for the cell $Cr/Cr^{+3}$ (0.1M)// $Fe^{+2}$ (0.01M) /Fe is  

  1. 0.26 v  
  2.  0.492 v  
  3. –0.339 v  
  4. –0.26 v  

Group - B 

Give a short answer to the following questions.   8 × 5=40 

1. Zinc blende is the major ore of Zinc  from where the metal is extracted by pyro metallurgical process.  

  1. Draw and explain vertical retort process for reduction of ZnO into Zn. [3]  
  2. Could we use sodium hydroxide to separate zinc and silver from each other? If yes, how? [1]  
  3. What happens when zinc is exposed to moist air for a long time? [1]  

2. Chemistry is in the service of mankind by providing food, clothes, shelter and employment.  Polymers, drugs, dyes, fertilizer, pesticides etc. are some of the chemicals in the service of  mankind.  

  1. What is polymerization? Write the name of monomers and reaction involves in the  preparation of polyester. [1+1+1]  
  2. What are ideal requirements for a dye? Azobenzene is a colored compound but not a dye  Explain. [1+1]  

3. Transition elements are defined as elements that have partially filled d- orbitals.  

  1. Why $[Ti(H_2O)_6]^{3+}$+ is violet in color in $[Ti(H_2O)_6]Cl_3$,but when water molecules are removed it  becomes colorless? [1]  
  2. What is d-orbital degeneracy? [1]  
  3. $K_4$[Fe$(CN)_6$], Potassium hexacyanoferrate (II) is a complex salt formed by iron. Write the  complex ion present in it. [1]  
  4. Give a possible reason for the fact that transition metals have high heat of atomization.[1] 
  5. A transition metal forms alloy with other transition metal easily, Explain.[1]  

4. The sum of the powers of concentration terms in the rate law equation is called the order of  reaction.  

  1. Write the three possible rate laws for the given second order reaction. [3]  A+ B→ product 
  2.  A reaction is of first order in reactant P and second order in reactant Q. How is the rate of  reaction affected when  
  1. Concentration of Q alone is increased 3 times.[1] 
  2. The concentrations of P as well as Q are doubled.[1]  

5. Limestone is a dominant raw material used for the manufacture of cement. When cement comes  in contact with water, it sets to hard mass showing exothermic reaction.  

  1. You are asked to bring 1500 tons of cement for the dam construction of a 400 MW  hydropower station. What type of cement do you prefer and why? [2]  
  2. While manufacturing the Portland cement, the % composition of MgO is not exceeded than  6%, why?[1]  
  3. After preparing the cement clinker it is cooled to a temperature of 60- $150^oC$ before grinding,  why?[1]  
  4. What is the role of $Fe_2O_3$ in the Portland cement?[1]  

6. Name reactions have great synthetic utility in organic chemistry, state the following name  reactions with correct example [5x1=5] 

  1.  Perkin condensation  
  2. Benzoin condensation  
  3. Wolff-Kishner reduction  
  4. Clemmenson’s reduction  
  5. Cannizzaro’s reaction  


Give suitable chemical reaction for the preparation of ethanoic acid from  

  1. Ethane nitrile  
  2. Methyl magnesium chloride  
  3. Ethanol  

Also, convert ethanoic acid to propanoic acid and vice-versa. [3+2]  

7. An organic compound ‘A’ reacts with sodium metal to give hydrogen gas. The compound A on  treatment with alkaline iodine forms yellow crystalline substance and on oxidation with acidified  potassium dichromate forms aldehyde with molecular formula C₂H₄O. Identify the compound  and write a chemical equation for these reactions. [5]  

8. 12 gm of impure Zinc is made to react with excess dilute $H_2SO_4$. The total volume of $H_2$ gas  liberated was found to be 4.2L at 570 mm of Hg pressure and 279K temperature. Determine the  percentage purity of Zinc.  


Common ion effect provides the most important method to monitor the concentration of  precipitant for the selective precipitation of metallic ions and solubility product principle helps to  predict whether the salt precipitates or not in qualitative analysis. 

Explain the application of Solubility product principle and common ion effect in qualitative salt  analysis. [5] 

Group - C 

Give long answer to the following questions  3 × 8 = 24  

9. In the laboratory, chloroform is prepared by reacting ethyl alcohol or acetone using bleaching  powder.  

  1. Write the principle reactions of oxidation, chlorination and hydrolysis processes for both  ethyl alcohol and acetone.  
  2. Why is chloroform always stored in a dark colored bottle?  
  3. Why was it used as an anesthetic drug in the past but nowadays it is discouraged?  
  4. Chloroform forms a chloretone drug with acetone in presence of aqueous alkali. Write the  chemical reaction and mention any one use of this drug.  
  5. What happens when chloroform reacts with conc. Nitric acid? Write an important  application of such a product. [2+1+1+2+2]  


An aromatic compound ‘A’ on diazotization gives compound ‘B’ which is warmed with water to  give compound ‘C’. The compound C is heated with acetyl chloride in presence of pyridine gives  ‘D’ which undergoes internal rearrangement in presence of anhydrous AlCl₃ and CS₂ as solvent  gives a mixture of ‘E’ and ‘F’. The compound C is heated with zinc dust to give parent  hydrocarbon benzene. Identify A, B, C, D, E and F with their name and suitable chemical  reaction involved for it.  

  1. What happens when compound C is heated with conc. HNO₃ and conc. H₂SO₄?
  2. Write any two important uses of Compound C. [6+1+1]  


  1. The solubility product of barium sulphate (BaSO4) is 1×10-10 at 298 K. Calculate its solubility in  
  1. pure water  
  2. $1×10^{-3}MH_2SO_4$ solution. [1+3]  

        b. Write the equation for the formation of naphthalene. Calculate the increase in entropy  in  the evaporation of 1 mole of water at 1000C. Given that the latent heat of vaporization  of water is 2.26 KJ$gm^{-1}$.[1+3]  

11. Aniline is the most common member of aromatic amines which is used to prepare drugs dyes  etc.  

  1. Prepare aniline from nitrobenzene. [1]  
  2. Aniline is less basic than aliphatic amine. Give a reason? [2]  
  3. Why is it necessary to protect the -$NH_2$ group before nitration of aniline? [1]  
  4. What is the diazotization reaction? Why is diazotization always carried out at ice cold  temperature? [2]  
  5. Convert Aniline into i) P-amino azobenzene ii) Acetanilide [2]  

SET- 5

Group -A 

Multiple Choice  Questions 11 x 11 = 11 

1. The mass of pure Na2CO3 having mol. Wt. 'M' required to prepare 100 mL of normal solution is

  1. M  
  2. M/2  
  3. M/10  
  4. M/20  

2. X, Y and Z have reduction potential values -0.52, -3.03 and -1.18 V respectively. The order of  reducing power is

  1. Y>Z>X 
  2. X>Y>Z 
  3. Z>Y>X 
  4. Z>X>Y  

3. Ionic product of water is  

  1. $10^{-7}$ m/L  
  2. $10^{-14}$ g/L  
  3. $10^{-7}$g/L  
  4. $10^{-14} mol2L-2 

4. What will be the rate of the reaction if temperature is increased from 30℃ to 100 ℃? 

  1. 70 times  
  2. 7 times  
  3. 64 times  
  4. 128 times  

5. The aldol condensation of A gives 3-hydroxybutanal, the compound A is  

  1. Ethanol  
  2. Methanol  
  3. Ethanal  
  4. Propanone  

6. Benzenediazonium chloride gives yellow dye when treated with phenol. The reaction is:

  1. Diazotization  
  2. Reimer-Tiemann  
  3. Coupling  
  4. Perkin  

7. Carboxylic acid is isomeric with  

  1. Alcohol  
  2. Aldehyde  
  3. Acid chloride  
  4. Ester  

8. Phenol reacts with nitrating mixture to give  

  1. Picric acid  
  2. Sulphonic acid  
  3. Salicylic acid  
  4. TNT 

9. What type of polymer is Nylon-6,6?  

  1. Co-polymer  
  2. Homopolymer  
  3. Condensation polymer  
  4. Synthetic polymer  

10. Cupellation is the process used in metallurgy of  

  1. Cu  
  2. Fe  
  3. Ag  
  4. Hg  

11. The trace metal present in insulin is  

  1. Fe  
  2. Cu  
  3. Zn  
  4. Hg  

Group- B 

Short Answer Questions  8 x 5 = 40 

1. Standard solution of $Na_2CO_3$ is used to determine the strength of $H_2SO_4$ during titration.

  1. How is the completion of reaction in this titration detected? If the solution prepared from  $Na_2CO_3$ is the primary standard? Why? [1+1]  
  2. 2.16 g of pure $Na_2CO_3$ is added to 400 mL of decinormal solution of $H_2SO_4$. How many grams  of $H_2SO_4$ is further required to neutralize the resultant solution completely? [3]  

2. Mention the important application of SHE. Predict spontaneity of the following reaction. 



The orange juice contains maleic acid ($C_5H_6O_5$), which can be estimated using a titration method.

  1. Mention the standard solution and indicator that may be used here.  
  2. Justify the use of a particular indicator mentioned in (a).  
  3. If concentration of solution is found to be x M, what will be its concentration in g/L?
  4. What might be the advantage of the result of this experiment in daily life?  

3. Explain the process to obtain blister copper from copper pyrite ($CuFeS_2$). [5] 

4Predict the structure and draw the shape of [$Cu(NH_3)_4]^{2+}$]. Define the term ligand. Why do most transition metals show catalytic properties? [2+1+2] 

5. What happens when phenol reacts with  

  1. Zn 
  2. $CHCL_3$
  3. phthalic anhydride 
  4. $FeCL_3$ 
  5. aq. $Br_2$


Write any 2/2 reactions that you can utilize to:  

  1.  Increase chain length of C in organic compounds. 
  2. To decrease the chain length of C in organic compounds.  

What happens when methanol is treated with ammonia? [2+2+1]  

6. A list of compounds is given below: 

p-hydroxyazobenzene, $C_6H_5N_2Cl, C_6H_5NO_2, C_6H_6, C_6H_5NH_2$

From within this above list of compounds prepare a sequence of chains with suitable conditions  and reactions. [5]  

7. Draw flow-sheet diagrams of paper production. A bone sample recovered from excavation is found  to have decay rate of C-14 to be 10 dis/min per gram of C and that for living plants is 15.3 dis /min  per gram of C. Determine the age of sample. Given half-life of C-14 is 5760 yrs. [2+3] 

8. Write a function each of gypsum, naphthalene and vinyl resin in cement. What are insecticides?  Write the structure of DDT. [3+2]  

Group - C 

Long Answer Questions  8 x 3 = 24 

9. A compound (A) undergoes reaction with aq. NaOH to give sodium benzoate and benzyl alcohol.  Compound A can be obtained by the reaction of toluene with $CeO_2/H^+$ and widely used as a flavoring  agent in industries. Show the reaction involved. [8 x 1] 

  1. Write the reaction compound A with  sodium bisulphite
  2. What happens when compound A is treated with acetic anhydride and sodium acetate?  
  3. Show the reaction of compound A with HI and P4.  
  4. Which product is obtained by the reaction of compound A with chlorine at low temperature?
  5. Write the reaction of compound A with alc. KCN.  
  6. Convert compound A into benzene.  

10. (A) Define electrode potential. Why absolute value of the reduction potential of electrode cannot be  determined? [1+1]  

The standard electrode potential re gives as  

$E^oZn/Zn^{++} = +0.76V$                    $E^oFe^{3+}/ Fe^{2+} = 0.77V$

  1.  Construct a cell notation for galvanic cells indicating anode and cathode.  
  2. Calculate the standard e.m.f at 1M solution of ions.  
  3. Calculate free energy change in the reaction. [1+1+1]  

(B) Define degree of ionization. How does the common ion effect affect the degree of ionization of weak  electrolytes? Explain with suitable examples. [1+2]  

11. A particular organic reaction produced three isomeric amines of different degrees in the same  vessel. From mass and NMR spectroscopy, the molecular formula of the isomers was determined  to be $C_3H_9N.$.  

Formulate a suitable method to separate the isomers. [5]  

Explain why aniline must be protected before nitration.[2]  

Aniline reacts with chloroform in the presence of NaOH, writing a reaction for this test. [1] 


  1. Starting from compound P, how do the reactions proceed ahead to obtain T, which gives  benzene when heated with Zn dust. Where R is aniline. Complete the reaction sequence with  suitable conditions. [5×1]
  2. Arrange the following derivatives of carboxylic acid on increasing order of the reactivity.  $CH_3CH_2COOCH_3, CH_3CH_2CH_2COCl, CH_3CH_2CONH_2,(CH_3CO)_2O$. Show the behavior of the most  and least reactive derivative towards dil. HCl. [1+2]

Source: Kathmandu world school, Gundu, Bhaktapur 

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