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CHEMISTRY IN EVERYDAY LIFE1 mark questionQ-1 Define the term chemotherapy? Ans-Treatment of diseases using chemicals is called chemotherapy. Q-2 why do we require artificial sweetening agents? Ans- To reduce calorie intake. Q-3 what are main constiuent of Dettol? Ans-Choloroxylenol & Terpinol . Q-4 what type drug phenaticinis? Ans- It is antipyretics. Q-5 Name the drug that are used to control allergy? Ans- Antihistamines. Q-6Why is the use of aspartame limited to cold food and drinks? Ans- It is unstable at cooking temperature and decomposes. Q-7What is tranquilizers? Give an example? Ans-They is the drug used in stress, mild severe mental disease. Q-8 what type of drug chloramphenicol? Ans- It is broad spectrum antibiotic. Q-9Why is biothional is added to the toilet soap? Ans-It acts as antiseptics. Q-10 what are food preservatives? Ans-The substances that prevent spoilage of food due to microbial growth. e.g. - sodium benzonate.Q11 What is pathogen?Ans. An organism which causes disease.Q12 Name the macromolecules that are chosen as drug targets?Ans. Enzymes, Carbohydrates, nucleic acids and proteinsQ13 What forces are involved in holding drugs to active sites of enzymes?Ans H-bonds, ionic and vander waal forcesQ14 What is allosteric site?Ans. Some drugs do not bind to the enzymes active site. These bind to a different sites and thus change the shape of active sites, this different sites is called allosteric site.Q15 What are antagonists?Ans. The drugs that bind to receptor site and inhibit its natural functions.2 marks questionQ-1 Mention one important use of the following- (i) Equanil (ii)Sucrolose Ans- (i) Equanil- It is a tranquilizer. (ii) Sucrolose-It is an artificial sweetener. Q-2 Define the following and give one example- (i)Antipyretics (ii) Antibiotics Ans- (i) Antipyretics- Those drugs which reduce the temperature of feveral body are called Antipyretics. Eg - Paracetamol (ii) Antibiotics-The drugs which prevent the growth of other micro-organisms. Eg- Pencillin. Q-3 Name the medicines used for the treatment of the following- (i) Tuberculosis (ii) Typhoid Ans-(i)Tuberculosis- Sterptomycin (ii) Typhoid- Cholororophenicol Q-4 what are tincture of iodine? Ans- 2-3% iodine solution of alcohol water is called tincture of Iodine. It is a powerful antiseptics and is applied on wounds. Q- 5 What is artificial sweetening agent? Give two examples? Ans-The substances which give sweetening to food but don’t add calorie to our body. Eg- Saccharin, alitame. Q-6 How is synthetic detergents better than soaps? Ans- (i) Detergents can be used in hard water but soaps cannot be used. (ii) Detergents have a stronger cleansing action than soaps. Q-7 what are sulpha drugs? Give two examples? Ans- A group of drugs which are derivatives of sulphanilamide and are used in place of antibiotics is called sulpha drugs. Eg- sulphadizine, sulphanilamide. Q-8 what forces are involved in holding the active sites of the enzymes? Ans-The forces are involved in holding the active sites of the enzymes are hydrogen bonding , ionic bonding , dipole-dipole attractions or Vander waals force of attractions. Q-9 Describe the following giving an example in each case- (i) Edible colours (ii) Antifertility drugsAns- (i) Edible colours- They are used for dying food. Eg- saffron is used to colour rice. (ii) Antifertility drugs- Those drugs which control the birth of the child are called antifertility drugs. Q-10 Give two examples of organic compounds used as antiseptics? Ans- Phenol (0.2%), iodoform 3 marks questionQ-1 what are Biodegredable and non-biodegdredable detergents? Give one example of each. Ans- Detergents having straight hydrocarbon chain and are easily decomposed by micro-organisms are called Biodegredable detergents.The detergents having branched hydrocarbon chain and are not easily decomposed by micro-organisms are called Non-Biodegredable detergents. Q-2 what are barbiturates? To which class of drugs do they belong? Give two examples. Ans-Derivatives of barbituric acid are called barbiturates.They are tranquilizers. They also act as hypnotics. eg- luminal , seconal. Q-3 what is the use of – (i) Benadryl (ii) sodium benzoate (iii) ProgesteroneAns- (i) Antihistamines (ii) Preservatives (iii) Antifertility drug Q-4 Identify the type of drug- (i) Ofloxacin (ii) Aspirin (iii) Cimetidine Ans- (i) Antibiotic (ii) Analgesics & Antipyretics (iii) Antihistamines & antacid Q-5 Describe the following with suitable example- (i) Disinfectant (ii) Analgesics (iii) Broad spectrum antibioticsAns. (i) Disinfectant- chemicals used to kill the micro-organisms can applied on non living articles. (ii) Analgesics- They are the drugs which are used to relieve pain . eg – Aspirin , Ibuprofen. (iii) Broad spectrum antibiotics- They kill the wide range of gram positive and gram negative bacteria. Eg- Chloramphenicol , ofloxacin.Q6. Pick out the odd one amongst the following on the basis of their medicinal properties. Give suitable reason. (i) Luminal, seconal, terfenadine, equanil. (ii) Chloroxylenol, phenol, chloamphenicol, bithional. (iii) Sucralose, aspartame, alitame, sodium benzoate. Ans. (i) Terfenadine is antihistamine other three are used as tranquilisers. (ii) Chloramphenicol is a broad spectrum antibiotic. Other three have antiseptic properties. (iii) Sodium benzoate is a food preservative. Other three are artificial sweetners.]Q7. Classify the following as cationic detergents, anionic detergents or nonionic detergents: (i) CH3 (CH2 ) 10 CH2 OSO3 – Na+ (ii) [CH3 – (CH2 ) 15 N(CH3 ) 3 ] + Br–Ans: (i) Anionic detergent. (ii) Cationic detergent.Q8. How do enzyme inhibitors work? Distinguish between competitive and noncompetitive enzyme inhibitors. Ans : An enzyme inhibitor either blocks the active site of enzyme or changes the shape of the active site by binding at an allosteric site. They are of two petitive enzyme inhibitor – It competes with natural substance for their attachment on the active sites of enzymes.Non-competitive enzyme inhibitor binds at allosteric site and changes the shape of the activesite in such a way that the substrate can not recognise it.Haloalkanes and HaloarenesQ1. Why haloalkanes are more reactive than haloarenes. Ans.(i) In haloarenes, there is double bond character b/w carbon and halogen due to resonance effect which makes him less reactive. (ii) In benzene, carbon being sp2 hybridised which is smaller in size than sp3 present in haloalkanes . So C-Cl bond in aryl halides is shorter and stronger.Q2. Why do haloalkenes under go nucleophillic substitution whereas haloarenes under go electophillic substitution . Ans. Due to more electro negative nature of halide atom in haloalkanes carbon atom becomes slightly positive and is easily attacked by nucleophillic reagents. While in haloarenes due to resonance, carbon atom becomes slightly negative and attacked by electrophillic reagents. Q3. When an alkyl halide is treated with ethanolic solution of KCN, the major product is alkyl cyanide where as if alkyl halide is treated with AgCN,the major product is alkyl isocyanide. Ans. KCN is ionic they can attach through C or N but C-C bond is strong than C-N bond. So alkyl cyanide is the major product but AgCN is covalent so more electronegative N can attach to C and forms isocyanides. Q4. How do 10, 20,30 alcohols differ in terms of dehydrogenation? Ans. 10 alcohol aldehyde , 20alcohol ketone Cu,3000 c Cu,3000 c, 30alcohol alkene Cu,3000 C Q5. Why are the reaction of alcohol /phenol with acid chloride in the presence of pyridine ? Ans. Because esterification reaction is reversible and presence of base (pyridine ) nuetralises HCl produced during reaction thus promoting forward reaction . Q6. Explain why o-nitrophenol is more acidic than o-methoxy phenol ? Ans. -NO2 group is electron with - drawing group, e- density on O decreases and loss of H+ is easy whereas –OCH3 group is electron releasing group , which increases e- density on O , which makes difficult to the loss of H+, hence are less acidic . Q6. Aryl halides cannot be prepared by the action of sodium halide in the presence H2SO4 .Why? Ans. Due to resonance the carbon- oxygen bond in phenols has partial double bond and it is stronger than carbon oxygen single bond. Q8. Why Grignard reagent should be prepared under an hydrous conditions.? Ans. Grignard reagent react with H2O to form alkenes , therefore they are prepared under anhydrous condition. Q7. Why is Sulphuric acid not used during the reaction of alcohols with KI?Ans. It is because HI formed will get oxidized to I2 by concentrated Sulphuric acid which is an oxidizing agent. Q8. p- dichlorobenzene has highest m.p. than those of ortho and m-isomers.? Ans. p- dichlorobenzene is symmetrical, fits into crystal lattice more readily and has higher melting point. Q9. Although chlorine is an electron- withdrawing group, yet it is ortho and para directing in electrophillic aromatic substitution reactions.Why Ans. Chlorobenzene is resonance hybrid, there is –ve charge at ortho and para positions, electrophillic substitution reaction will take place at ortho and para position due to +R effect. +R effect is dominating over – I effectQ10. The treatment of alkyl chlorides with aqueous KOH lead to the formation of alcohols but in presence of alcoholic KOH alkenes are major products. Explain? Ans. In aqueous KOH,OH- is nucleophile which replaces another nucleophile. R-X +KOH → R-OH +KX Where as in alcoholic KOH C2H5OH +KOH C2H5O- + K+ CH3CH2-Cl + alcoholic KOH CH2 =CH2 + C2H5OH (C2H5O- ) Q11. Explain why vinyl chloride is unreactive in nucleophillic substitution reaction? Ans. Vinyl chloride is unreactive in nucleophillic substitution reaction because of double bond character between C=CL bond which is difficult to break. CH2 = CH – Cl CH2 - –CH =Cl+ Q14. Arrange the following compounds according to reactivity towards nucleophillic substitution reaction with reagents mentioned :- (i) 4- nitro chloro benzene, 2,4 di nitro chloro bemzene, 2,4,6, trinitrochlorobenzene with CH3ONa Ans- 2,4,6, trinitrochlorobenzene > 2,4 dinitrochlorobemzene > 4- nitrochlorobenzene3 MARKS QUESTIONS Q1. How can we produce nitro benzene from phenol? Ans. (I) First convert phenol to benzene by heating with Zn dust. (II) Nitration of benzene with conc. nitric acid in presence of conc. sulphuric acid.Q 2. Alcohols reacts with halogen acids to form haloalkenes but phenol does not form halobenzene. Explain . Ans. The C-O bond in phenol acquires partial double bond character due to resonance and hence be cleared by X- ions to form halobenzenes. But in alcohols a pure C — O bond is maintained and can be cleared by X– ions. Q 3. Explain why o-nitrophenol is more acidic than o-methoxy phenol? Ans . Due to — R and — I effect of — NO2 group, e– density on ?O‘ if O — H bond decreases and loss of H+ is easy.– I effect In contrast, in o-methoxy phenol due to + R effect, – OCH3 increases. e– density on O2 of O—H group, and hence loss of H+ is difficult.(both –ve charge repel each other) Q4. Of benzene and phenol, which is more easily nitrated and why? Ans. Nitration is an electrophilic substitution. The –OH group in phenol increases the electron density at ortho and para position as follows Since phenol has higher electron density due to electron releasing nature of -OH group , compared to benzene , therefore nitration is easy in phenol than benzene. Q5. How will you account for the following? Ethers possess a net dipole moment even if they are symmetrical in structure? A. Because of greater electronegativity of o- atom than carbon C – O bonds are polar. C – O bond are inclined to each other at an angle of 110° (or more), two dipoles do not cancel out each other. Q 6. How do 1°, 2° and 3° alcohols differ in terms of their oxidation reaction and dehydrogenation ? Ans. (I) Oxidation reaction : (O) (O) 1° alcohol → aldehyde → carboxylic acid (O) (O) 2° alcohol→ ketone → carboxylic acid (acid with loss of 1 carbon atom) (O) 3° alcohol→ resistant to oxidation (II) Hydrogenation reaction : give 1° alcohol → aldehyde 2° alcohol → ketone 3° alcohol → alkene 3° alcohols prefer to undergo dehydration and form alken Q7. (i)How is diethyl ether prepared from ethyl alcohol? Ans. Ethyl alcohol is first treated with sodium to form sodium ethoxide C2H5OH + Na C2H5O– Na+ + H2 Sodium ethoxide is then treated with ethyl halide to form di ethyl ether. SN? C2H5O Na + — C2H5X → C2H5O C2H5 + NaX (Williamson synthesis) (II) Complete the reaction: (a) CH3OCH3 + PCl5 ? (b) C2H5OCH3 + HCl ? (c) (C2H5)2 O + HCl A. (a) 2 CH3Cl (b) CH3Cl + C2H5OH (c) C2H5Cl + C2H5OH Q8. Why are reactions of alcohol/phenol and with acid chloride in the presence of pyridine? Ans. Because esterification reaction is reversible and presence of base (pyridine) neutralises HCl produced during reaction thus promoting forward reaction. ................
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