Important Questions for Board Exam
Practice Questions:
1. Which point defect in crystals does not change the density of the relevant solid ?
2. Which point defect in its crystal units change the density of a solid ?
3. Which point defect in its crystal units increases the density of a solid ?
4. How do metallic and ionic substances differ in conducting electricity ?
5. What is the number of atoms in a unit cell of a face-centred cubic crystal ?
6. Write a feature which will distinguish a metallic solid from an ionic solid.
7. What type of interactions hold the molecules together in a polar molecular solid ?
8. What type of semiconductor is obtained when silicon is doped with arsenic ?
9. Crystalline solids are anisotropic in nature.’ What does this statement mean ?
10. Write a distinguishing feature of metallic solids.
11. What is meant by ‘doping’ in a semiconductor ?
12. Write a point of distinction between a metallic solid and an ionic solid other than metallic lustre.
13. How may the conductivity of an intrinsic semiconductor be increased ?
14. Which stoichiometric defect increases the density of a solid ?
15. What are n-type semiconductors ?
Practice Questions:
1. Differentiate between molarity and molality of a solution.
2. What is meant by Reverse Osmosis ?
3. What is meant by Osmosis ?
4. What are isotonic solutions ?
5. Some liquids on mixing form ‘azeotropes’. What are ‘azeotropes’?
6. What type of intermolecular attractive interaction exists in the pair of methanol and acetone?
7. Define the terms, ‘osmosis’ and ‘osmotic pressure’.
8. Explain why aquatic species are more comfortable in cold water rather than in warm water.
9. State Henry’s law and mention two of its important applications.
10. State Raoult’s law. How is it formulated for solutions of non-volatile solutes ?
11. Why do gases nearly always tend to be less soluble in liquids as the temperature is raised?
12. An aqueous solution of sodium chloride freezes below 273 K. Explain the lowering in freezing points of water with the help of a suitable diagram.
13. Derive expression for Raoult’s law when the solute is non-volatile.
14. Define an ideal solution and write one of its characteristics.
15. State Henry’s law. What is the effect of temperature on the solubility of a gas in a liquid?
Practice Questions:
1. What is meant by ‘limiting molar conductivity’?
2. Express the relation between conductivity and molar conductivity of a solution held in a cell.
3. Express the relation among the cell constant, the resistance of the solution in the cell and the conductivity of the solution. How is the conductivity of a solution related to its molar conductivity ?
4. Write the reactions taking place at cathode and anode in lead storage battery when the battery is in use. What happens on charging the battery ?
5. The conductivity of 0.20 M solution of KCl at 298 K is 0.025 S cm-1. Calculate its molar conductivity.
6. The standard electrode potential (E°) for Daniel cell is +1.1 V. Calculate the ΔG° for the reaction
Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
(1 F = 96500 C mol-1).
7. The standard electrode potential for Daniell cell is 1.1 V. Calculate the standard Gibbs energy for the cell reaction. (F = 96,500 C mol-1)
8. State Kohlrausch law of independent migration of ions. Why does the conductivity of a solution decrease with dilution?
9. Calculate the time to deposit 1.27 g of copper at cathode when a current of 2A was passed through the solution of CuSO4.
(Molar mass of Cu = 63.5 g mol-1,1 F = 96500 C mol-1)
10. Calculate the degree of dissociation (a) of acetic acid if its molar conductivity (Λm) is 39.05 S cm2 mol-1.
Given: λ°(H+) = 349.6 S cm2 mol-1 and λ°(CH3COO–) = 40.9 S cm2 mol-1
11. Write the name of the cell which is generally used in hearing aids. Write the reactions taking place at the anode and the cathode of this cell.
12. Write the name of the cell which is generally used in transistors. Write the reactions taking place at the anode and the cathode of this cell.
13. Write the name of the cell which is generally used in inverters. Write the reactions taking place at the anode and the cathode of this cell.
14. What are fuel cells? Explain the electrode reactions involved in the working of H2 – O2 fuel cell.
15. How much electricity in terms of Faradays is required to produce 20 g of calcium from molten CaCl2 ?
Practice Questions:
1. Define ‘rate of a reaction’
2. Define ‘order of a reaction’.
3. Define ‘activation energy’ of a reaction.
4. Express the rate of the following reaction in terms of the formation of ammonia :
N2(g) + 3H2(g) → 2NH3(g)
5. If the rate constant of a reaction is k = 3 × 10-4 s-1, then identify the order of the reaction.
6. Write the unit of rate constant for a zero order reaction.
7. Define rate constant (K).
8. For a reaction R → P, half-life (t1/2) is observed to be independent of the initial concentration of reactants. What is the order of reaction?
9. Explain Elementary step in a reaction
10What do you understand by the rate law and rate constant of a reaction? Identify the order of a reaction if the units of its rate constant are :
(i) L-1 mol s-1 (ii) L mol-1 s-1
11. What is meant by rate of a reaction? Differentiate between average rate and instantaneous rate of a reaction.
12. Rate constant k for a first order reaction has been found to be 2.54 × 10-3 sec-1. Calculate its 3/4th life, (log 4 = 0.6020).
13. Write two differences between ‘order of reaction’ and ‘molecularity of reaction’.
14. Define the following terms :
a. Pseudo first order reaction.
b. Half life period of reaction (t1/2).
15.Define the following terms :
a. Pseudo first order reaction.
b. Half life period of reaction (t1/2).
c. Specific rate of a reaction
Practice Questions:
1. Write any two characteristics of Chemisorption.
2. Why does physisorption decrease with the increase of temperature?
3. Why are powdered substances more effective as adsorbents than their crystalline forms?
4. Why is the ester-hydrolysis slow in the beginning and becomes faster after sometime?
5. What is the role of desorption in the process of catalysis?
6. What modification can you suggest in the Hardy Schulze, law?
7. Why is it essential to wash a precipitate with water before estimating it quantitatively?
8. What is the difference between physical adsorption and chemisorption ?
9. What are the factors which influence the adsorption of a gas on a solid?
10. What is an adsorption isotherm? Describe Freundlich adsorption isotherm.
11. What do you understand by activation of adsorbent ? How is it achieved?
12. Why is adsorption always exothermic?
13. Discuss the effect of pressure and temperature on the adsorption of gases on solids.
14. What is the difference between multimolecular and macromolecular colloids? Give one example of each.
15. What are enzymes? Write in brief the mechanism of enzyme catalysis.
Practice Questions:
1. Copper can be extracted by hydrometallurgy but not zinc. Explain.
2. What is the role of depressant in froth-floatation process?
3. Why is the extraction of copper from pyrites more difficult than that from its oxide ore through reduction?
4. Out of C and CO which is a better reducing agent at 673 K?
5. Name the common elements present in anode mud in the electro-refining of copper. Why are they so present?
6. Write down the reactions taking place in different zones in the blast furnace during the extraction of iron.
7. Write chemical reactions taking place in the extraction of zinc from zinc blende.
8. State the role of silica in the metallurgy of copper.
9. What is meant by the term “chromatography”?
10. What criterion is followed for the selection of the stationary phase in chromatography?
11. Describe a method for refining nickel.
12. How can you separate alumina from silica in a bauxite ore associated with silica? Give equations, if any.
13. How can you separate alumina from silica in a bauxite ore associated with silica? Give equations, if any.
14. How is ‘cast-iron’ different from ‘pig iron’?
15. Differentiate between “minerals” and “ores’.
Practice Questions:
Practice Questions:
Practice Questions:
1. Give two examples of ligands which form coordination compounds useful in analytical chemistry.
2. Which of the following is more stable complex and why ?
[Co(NH3)6]3+ and [Co(en)3]3+
3. What is meant by chelate effect?
4. Why are low spin tetrahedral complexes not formed?
5. How is the stability of a co-ordination compound in solution decided ?
6. [Fe(H2O)6]3+ is strongly paramagnetic whereas [Fe(CN)6]3- is weakly paramagnetic. Explain.
7. Give an example of linkage isomerism.
8. Give an example of coordination isomerism.
9. Give an example of ionization isomerism.
10. Write down the formula of Tetraamineaquachloridocobalt(III) chloride.
11. Indicate the types of isomerisms exhibited by the complex [Co(NH3)5 (NO2)] (NO3)2.
12. What type of bonding helps in stabilishing the a-helix structure of proteins ?Which complex ion is formed when undecomposed AgBr is washed with hypo solution in photography ?
13. Give IUPAC name of the ionization isomer of [Ni(NH3)3NO3]Cl.
14. Explain why [Co(NH3)6]3+ is an inner orbital complex whereas [Ni(NH3)6]2+ is an outer orbital complex.
15. Write the IUPAC name of the complex [Cr(NH3)4Cl2]+. What type of isomerism does it exhibit?
Practice Questions:
1. A solution of KOH hydrolyses CH3CHClCH2CH3 and CH3CH2CH2CH2Cl. Which one of these is more easily hydrolysed ?
2. Predict the order of reactivity of the following compounds in SN1 reaction :
C6H5CH2Br, C6H5C(CH3) (C6H5)Br, C6H5CH(C6H5)Br, C6H5CH(CH3)Br
3. Give a chemical test to distinguish between C2H5Br and C6H5Br.
4. Arrange the following in increasing order of boiling point:
a. CH3CH2CH2CH2Br
b. (CH3)3.Br
c. (CH3)2CH.Br
5. What happens when CH3 — Br is treated with KCN ?
6. What happens when ethyl chloride is treated with aqueous KOH ?
7. A hydrocarbon C5H12 gives only one mono-chlorination product. Identify the hydrocarbon.
8. Write the structure of an isomer of compound C4H9Br which is most reactive towards SN1 reaction.
9. How are the following conversions carried out ?
a. Benzyl chloride to benzyl alcohol
b. Methyl magnesium bromide to 2-methyl- propan-2-ol
10. Haloalkanes undergo nucleophilic substitution whereas haloarenes undergo electrophilic substitution. Explain.
11. Chlorobenzene is extremely less reactive towards a nucleophilic substitution reaction. Give two reasons for the same.
12. Why does p-dichlorobenzene have a higher m.p. than its o- and m-isomers ?
13. Why is (±)-Butan-2-ol optically inactive ?
14. Account for the following:
a. The C – Cl bond length in chlorobenzene is shorter than that in CH3 – Cl.
b. Chloroform is stored in closed dark brown bottles.
15. Give chemical tests to distinguish between the following pairs of compounds :
a. Benzyl chloride and Chlorobenzene
b. Chloroform and Carbon tetrachloride
Practice Questions:
Practice Questions:
Practice Questions:
1. Why is an alkylamine more basic than ammonia ?
2. Arrange the following compounds in an increasing order of basic strengths in their aqueous solutions:
NH3, CH3NH2, (CH3)2NH, (CH3)3N
3. Give the IUPAC name of H2N — CH2—CH2—CH = CH2.
4. Arrange the following compounds in an increasing order of their solubility in water:
C6H5NH2, (C2H5)2NH, C2H5NH2
5. Give a chemical test to distinguish between ethylamine and aniline.
6. Write the structure of 2-aminotoluene.
7. Write the structure of n-methylethanamine.
8. Write the structure of prop-2-en-l-amine.
9. How may methyl bromide be preferentially converted to methyl isocyanide ?
10. The conversion of primary aromatic amines into diazonium salts is known as
11. Out of CH3—NH2 and (CH3)3N, which one has higher boiling point?
12. Arrange the following in increasing order of basic strength-
Aniline, p-Nitroaniline and p-Toluidine
13. Give the chemical tests to distinguish between the following pairs of compounds :
a. Ethyl amine and Aniline
b. Aniline and Benzylamine
14. Give the chemical tests to distinguish between the following pairs of compounds:
a. Methylamine and Dimethylamine
b. Aniline and N-methylaniline
15. Give chemical tests to distinguish between the following pairs of compounds:
a. Aniline and Ethylamine
b. Ethylamine and Dimethylamine
Practice Questions:
1. What is meant by ‘reducing sugars’?
2. What are monosaccharides?
3. Write the structure of the product obtained when glucose is oxidised with nitric acid.
4. Write a reaction which shows that all the carbon atoms in glucose are linked in a straight chain.
5. What are the expected products of hydrolysis of lactose ?
6. Where does the water present in the egg go after boiling the egg?
7. Name a water soluble vitamin which is a powerful antioxidant. Give its one natural source.
8. What are three types of RNA molecules which perform different functions?
9. What is a glycosidic linkage?
10. What are the products of hydrolysis of sucrose?
11. Name a water soluble vitamin which is a powerful antioxidant. Give its one natural source.
12. Write the name of linkage joining two amino acids.
13. Name the deficiency diseases resulting from lack of Vitamins A and E in the diet.
14. Name one water soluble vitamin which is a powerful antioxidant. Give its one natural source.
15. Name one oil soluble vitamin which is a powerful antioxidant and give its one natural source.
16. Mention one important function of nucleic acids in our body.
17. Which of the two components of starch is water soluble?
18. Which component of starch is a branched polymer of a-glucose and insoluble in water?
19. What are enzymes?
20. Name two water soluble vitamins, their sources and the diseases caused due to their deficiency in diet.
21. What are essential and non-essential amino acids in human food? Give one example of each type.
22. State clearly what are known as nucleosides and nucleotides.
Describe what you understand by primary structure and secondary structure of proteins.
23. Why are vitamin A and vitamin C essential for us?
24. Amino acids may be acidic, alkaline or neutral. How does this happen? What are essential and non-essential amino acids? Name one of each type.
25. Write the structural and functional differences between DNA and RNA
Give two differences between globular and fibrous proteins.
26. How are hormones and vitamins different in respect of their source and functions?
27. How are nucleosides different from nucleotides?
Practice Questions:
1. What are polymers?
2. How are polymers classified on the basis of structure?
3. Explain the difference between Buna-N and Buna-S.
4. Arrange the following polymers in increasing order of their intermolecuiar forces.
a. Nylon 6,6, Buna-S, Polythene
b. Nylon 6, Neoprene, Polyvinyl chloride
5. What are natural and synthetic polymers ? Give two examples of each.
6. Distinguish between the terms homopolymer and copolymer and give an example of each.
7. How do you explain the functionality of a monomer?
8. Define the term polymerisation?
9. Is (-NH — CHR—CO-)n a homopolymer or copolymer?
10. In which classes, are the polymers classified on the basis of molecular forces?
11. How can you differentiate between addition and condensation polymerisatiop?
12. Explain the term copolymerisation and give two examples.
13. Write the free radical mechanism for the polymerisation of ethene.
14. Define thermoplastics and thermo setting polymers with two examples of each
15. Write the monomers used for gettingThe following polymers:
a. Polyvinylchloride
b. Teflon
c. Bakelite
Practice Questions:
1. Differentiate between disinfectants and antiseptics.
2. What are limited spectrum antibiotics? Give one example.
3. Name the important by-products of soap industry.
4. Why do we require artificial sweetening agents ?
5. What are food preservatives? Name two such substances.
6. Explain the cleaning action of soap. Why do soaps not work in hard water ?
7. What are Cationic detergents and Anionic detergents ?
8. Explain the following types of substances with one suitable example, for each case-
a. Food preservatives
b. Analgesics
9. What are analgesic medicines ? How are they classified and when are they commonly recommended for use ?
10. Explain the following terms with one suitable example in each case-
a. Enzymes
b. Antifertility drugs
11. Why do soaps not work in hard water ?
12. What are the main constituents of dettol ?
13. What is tincture of iodine and what is it used for ?
14. What are the following substances? Give one example of each one of them-
a. Tranquilizers
b. Synthetic detergents
c. Narcotic analgesics
15. What is Broad spectrum antibiotics ?
16. Why is bithional added to soap ?
17. Which class of drugs is used in sleeping pills ?
18. What class of drug is Ranitidine ?
19. If water contains dissolved Ca2+ ions, out of soaps and synthetic detergents, which will you use for cleaning clothes ?
20. Give two examples of macromolecules that are chosen as drug targets.
21. What are antiseptics ? Give an example.
22. Why is use of aspartame limited to cold foods and soft drinks ?
23. Name the sweetening agent used in the preparation of sweets for a diabetic patient.
24. What are biodegradable and non-biodegradable detergents? Give one example of each.
25. Why should medicines not be taken without consulting a doctor ?
26. What are the main constituents of Dettol ?
27. Why is the use of aspartame limited to cold foods and drinks ?
28. Write the therapeutic action of following on human body and mention the class of drugs to which each of these belong:
a. Ranitidine
b. Morphine
c. Aspirin
29. Write the therapeutic action of following on human body and mention the class of drugs to which each of the these belong:
a. Equanil
b. Aspirin
c. Chloramphenicol
30. Name a substance which can be used as an antiseptic as well as disinfectant.