Bihar Board Class 12 Chemistry Solutions Chapter 16 Chemistry in Everyday Life Textbook Questions and Answers, Additional Important Questions, Notes.
BSEB Bihar Board Class 12 Chemistry Solutions Chapter 16 Chemistry in Everyday Life
Bihar Board Class 12 Chemistry Chemistry in Everyday Life Intext Questions and Answers
Question 1.
Sleeping pills are recommended by doctors to the patients ‘ suffering from sleeplessness, but it is not advisable to take its doses without consultation with doctor. Why?
Answer:
Most of the drugs taken in higher doses than recommended may cause harmful effect and act as poison. Excess of dosage of sleeping pills may prove fatal. Therefore, a doctor must always be consulted for appropriate dose before taking medicine.
Question 2.
With reference to which classification has the statement, “ranitidine is an antacid.” been given.
Answer:
It belongs to antacid group of medicines to control acidity. This statement refers to the classification according to pharmacological effect of the drug as it counteracts the effect of excess of acid in the stomach.
Question 3.
Why do we require artificial sweetening agents?
Answer:
Natural sweeteners like glucose, sucrose etc. add to calorie intake and therefore many people prefer to use artificial sweeteners. They are of great value to diabetic persons and people who are calorie-conscious. They are excreted from the body in the urine unchanged.
Question 4.
Write the chemical equation for preparing sodium soap from glyceryl oleate and glyceryl palmitate. Structural formulae of these compounds are given below.
(i) (C15H31COO)3 C3H5 – Glyceryl palmitate
(ii) (C17H33COO)3 C3H5 – Glyceryl oleate
Answer:
These glycerides on hydrolysis with NaOH (called Saponification) give soaps.
Question 5.
Following type of non-ionic detergents are present in liquid detergents, emulsifying agents and wetting agents. Label the hydrophilic and hydrophobic parts in the molecule. Identify the functional group (s) present in the molecule.
Answer:
Bihar Board Class 12 Chemistry Chemistry in Everyday Life Text Book Questions and Answers
Question 1.
Why do we need to classify drugs in different ways?
Answer:
Drugs are classified according to their effects on different elements of the human body. Drugs classification is useful for doctors. For example, analgesics have painkilling effect, whereas antiseptics kill or arrest the growth of microorganisms.
Question 2.
Explain the term, target molecules or drug targets as used in medicinal chemistry.
Answer:
Target molecules or drug targets-Drugs usually interact with biological macromolecules such as carbohydrates, lipids proteins and nucleic acids. These biological molecules are called targets. The correct choice of the molecular target for a drug is important to obtain its desired therapeutic effect.
Question 3.
Name the macromolecules that are chosen as drug targets.
Answer:
Macromolecules that are chosen as drug targets include carbohydrates, lipids, proteins and nucleic acids.
Question 4.
Why should not medicines be taken without consulting doctors?
Answer:
Medicines should always be taken at the advice of the doctors. Medicines affect human metabolism and provide cure from different ciilments of the body. A medicine wrongly taken without the consultation of a doctor may not be effective or may have serious side effects. In larger doses, they may have a poisonous effect.
Question 5.
Define the term Chemotherapy.
Answer:
Use of chemicals in prescribed doses for therapeutical effect is called Chemotherapy.
Question 6.
Which forces are involved in holding the drugs, to the active site of enzymes?
Answer:
Active sites of enzymes hold the drug through a variety of interactions such as ionic bonding, hydrogen bonding, van der waals interactions or dipole-dipole interactions.
Question 7.
While antacids and antiallergic drugs interfere with the function of histamines, why do these not interfere with the function of each other.
Answer:
Both antacids and antiallergic drugs interfere with the function of histamine. Antacid like Cimetidine was designed to prevent the interaction of histamine with the receptors present in the stomach wall [this resulted in release of lesser amount of acid.] Antacid and antiallergic drugs work on different receptors.
Question 8.
Low level of noradrenaline is the cause of depression. What type of drugs are needed to cure this problem? Name two drugs.
Answer:
Noradrenaline is one of the neurotransmitters that plays role in mood changes. If its level is low, the signal-sending activity becomes low and the person suffers from depression. In such a situation, antidepressant drugs are required. These drugs inhibit the enzymes which catalyse the degradation of noradrenaline. If the enzyme is inhibited this important neurotransmitter is slowly metabolised and can activate its receptor for longer periods of time thus counteracting the effect of depression. Iproniazid and phenelzine are two such drugs.
Question 9.
What is instant by the term ‘broad-spectrum antibiotics? Explain.
Answer:
The full range of microorganisms attacked by an antibiotic is called its spectrum. Broad-spectrum antibiotics are medicines effective against several different types of harmful microorganisms, e.g., tetracycline, chloramphenicol and a mixture of potent antibiotics.
Question 10.
How do antiseptics differ from disinfectants? Give an example of each.
Answer:
Antiseptics and disinfectants are the chemicals which either kill or prevent the growth of microorganisms. Antiseptics are applied to the living tissues such as wounds, cuts, ulcers and diseased skin surfaces. Examples are furacine, soframicine. Disinfectants, on the other hand, are applied to inanimate objects such as floors, drainage system, instruments etc. Chlorine in the concentration of 0.2 to 0.4 ppm and SO2 in very small concentration are disinfectants.
Question 11.
Why are cinetidine and ranitidine better antacides than sodium bicarbonate or magnesium or aluminium hydroxide?
Answer:
Excessive sodium bicarbonate or magnesium or aluminium hydroxide can make the stomach alkaline and trigger the production of even more acid. It was discovered that histamine stimulates the secretion of pepsin and hydrochloric acid. The drugs cinetidine and rontidine were designed to prevent the interaction of histamine with the receptors present in the stomach wall. This resulted in release of lesser amount of acid.
Question 12.
Name a substance which can be used as an antiseptic as well as disinfectant.
Answer:
0.2 per cent solution of phenol is an antiseptic while its one per cent solution is disinfectant.
Question 13.
What are main constituents of Dettol? –
Answer:
Dettol is a mixture of chloroxylenol and terpineol in a suitable solvent.
Question 14.
What is tincture of iodine? What is its use?
Answer:
It is 2-3 % solution of iodine in alcohol and water. It is a powerful antiseptic.
Question 15.
What are food preservatives?
Answer:
Food preservatives prevent spoilage of food due to microbial growth. Table salt, sugar and vegetable oils are class I preservatives. The most common preservative of class II is sodium benzoate [C6H5CO0Na]. It can be safely used in small quantities which is metabolised in body.
Question 16.
Why is use of aspartame limited to cold foods and fruits?
Answer:
The use of aspartame as an artificial sweeter is limited to cold foods and cold drinks because it is unstable to heat and decomposes at cooking temperature.
Question 17.
What are artificial sweetening agents? Give two examples.
Answer:
Sucrose, glucose etc. are natural sugars. They add to calorie intake. To cut down on the intake of calories many people use artificial sweeteners such as saccharine (ortho-Sulpho-benzamide) which is 550 times as sweet as sugar (mass to mass) with negligible calories. It is excreted from the body in urine unchanged. It. is entirely inert and harmless when taken. It is of great value to diabetic persons and people who need to control intake of calories. Other example of artificial sweeteners are aspartame, sucrose, all tame.
Question 18.
Name the sweetening agent used in the preparation of sweet for a diabetic patient.
Answer:
Sucrolose which is trichloro derivative of sucrose and has appearance and tastes like sugar is stable at cooking temperature. It is a zero-calorie sweetener.
Question 19.
What problem arises in using alitame as artificial sweetener?
Answer:
Alitame is high potency sweetener (Mass per mass it is 2000 times sweeter than can sugar). The control of sweetness of food is difficult while using it.
Question 20.
How are synthetic detergents better than soap?
Answer:
Soaps when used in hard water form curdy precipitate that separates as scum. These insoluble soaps are useless as cleansing agent. Synthetic detergents, on the other hand, can be used in any sort of water because they form foam even in water containing mineral compounds. Some of them can give foam even in ice-cold water.
Question 21.
Explain the following terms with suitable examples.
(a) cationic detergents, (b) anionic detergents and (c) neutral detergents.
Answer:
(a) Cationic detergents-They are acetates, chlorides or bromides of quaternary ammonium salts. Cationic part possesses a long hydrocarbon chain and a positive charge. Hence these are called cationic detergents. Example is cetylmethyl ammonium bromide whose structure is given.
(b) Anionic detergents-Anionic detergents are sodium salts of sulphonated long-chain alcohols. Alkyl hydrogen sulphonates formed by treating long-chain alcohols with concentrated sulphuric acid are neutralised with alkali to form anionic detergents. Sodium lauryl sulphonate CH3 (CH2)10 CH2O , SO3– Na+ is an example. In anionic detergents, anionic part of the molecule is involved in die cleansing action. They are also used in toothpastes.
(c) Neutral detergents-Stearic add reacts with polyethene glycol to form non-ionic /neutral detergents.
Liquid dishwashing detergents are non-ionic type.
Question 22.
What are biodegradable and non-biodegradable detergents? Give one example of each.
Answer:
Detergents having straight hydrocarbon chains are easily degraded (or decomposed) by microorganisms and hence are called biodegradable detergents while detergents containing branched hydrocarbon chains are not easily degraded by the microorganisms and hence are called non-biodegradable detergents.
Sodium alkyl sulphates like sodium lauryl sulphate is 100 % biodegradable.
Examples of hard or non-biodegradable detergent is alkylbenzene sulphonate (branched chain)
Question 23.
Why do soaps not work in hard water?
Answer:
Hard water contains calcium and magnesium ions. These form insoluble calcium and magnesium soaps respectively.
These insoluble soaps are useless as cleansing agent. In fact these are hindrances to good washing because this precipitate adheres on to the fibres of the cloth as gummy mass.
Question 24.
Can you use soaps and synthetic detergents to check the hardness of water?
Answer:
Soaps and detergents can be used to check the hardness of water. Hard water forms curdy white precipitate with Ca2+ and Mg2+ ions present in hard water where as no such precipitates are formed by detergents in hard water.
Question 25.
Explain the cleansing action of soaps.
Answer:
All the soaps and detergents contain two characteristic groups, i.e., a water-soluble (hydrophilic) group and oil-soluble (Lyophilic or lipophilic group). As a result one end of the molecule of a soap or detergent tends to go into oil phase and the other end tends to go into water phase with the net result that the material (soap or detergent) concentrates at the surface of the solution or interace.
The dirt is generally held to a dirty surface by a thin film of an oil or grease. When it is treated with soap solution, the non-polar hydrocarbon chain of soap or detergent dissolves in oil or grease and the carboxylate part of the soap or the sulphonate group of the detergent is held by surrounding water (in fig. below). This lowers the surface tension between water and grease. As a result, a stable emulsion of oil in water is formed. When the surface or the cloth is mechanically scrubbed the loosened dirt particles are absorbed by colloidal soap particles and ultimately washed away by water.
Question 26.
If water contains dissolved calcium bicarbonate, out of soaps and synthetic detergents which one will you use for cleansing clothes?
Answer:
Synthetic detergents.
Question 27.
Label the hydrophilic and hydrophobic parts in the following compounds.
(c) CH3 (CH2)16 COO (CH2CH2O)n CH2CH2OH
Answer:
Bihar Board Class 12 Chemistry Chemistry in Everyday Life Additional Important Questions and Answers
Very Short Answer Type Questions
Question 1.
Name a substance which can be used both as an antiseptic as well as disinfectant. (C.B.S.E. Sample Paper 1997)
Answer:
Phenol.
Question 2.
What is the name given to medicines used for getting relief from pain?
Answer:
Analgestic.
Question 3.
What is aspartame and what is its use?
Answer:
It is a dipeptide of phenylalanine and aspartic acid and is used as an artificial sweetener.
Question 4.
Name one antihistamine drug.
Answer:
Chlorpheniramine.
Question 5.
Name a drug used in mental depression. (D.S.B. 2001)
Answer:
Equanil or barbituric acid derivatives such as seconal.
Question 6.
What is the difference between a preservative and an antioxidant?
Answer:
Preservatives protect the food from spoilage by bacteria yeast and moulds but antioxidants prevent oxidation of fats in processed food.
Question 7.
Give one example of an (i) bactericidal antibiotic, (ii) bacteriostatic antibiotic.
Answer:
- Penicillin
- Tetracycline.
Question 8.
Name an antacid which prevents the formation of acid in the stomach.
Answer:
Omeprazole or lansoprazole.
Question 9.
Write the name and structure of a medicine which is used for prevention of heart attacks.
Answer:
Question 10.
What structural unit makes detergents non-biodegradable?
Answer:
Branching in the long-chain hydrocarbon tail.
Question 11.
Why are synthetic detergents preferred to soaps.
Answer:
Unlike soaps, detergents can be used even in hard water, because like sodium salts, calcium and magnesium salts of sulphonic acids are soluble in water.
Question 12.
What are the consequences of using non-biodegradable detergents?
Answer:
Non-biodegradable detergents are decomposed very slowly by microorganisms. Therefore, they accumulate in water sources causing severe water pollution.
Question 13.
Give an example of as alpha drug.
Answer:
Sulphadiazine or Sulphaguanidine.
Question 14.
Define a transquiller.
Answer:
A drug which acts on the central nervous system (CNS) to help in reducing anxiety.
Question 15.
What type of drug is Chloramphenicol?
Answer:
It is a broad-spectrum antibiotic.
Question 16.
Name the antibiotic used specially for treatment of typhoid fever?
Answer:
Chloramphenicol.
Question 17.
What are the considerations in designing a drug?
Answer:
(i) Drug target and (ii) Drug metabolism.
Question 18.
Give the name and structure of a sulpha drug which is antibacterial.
Answer:
Question 19.
How do drugs interact with enzymes?
Answer:
Drugs inhibit the activities of enzymes.
Question 20.
What are neurotransmitters? What is their role?
Answer:
Neurotransmitters are small molecules such as acetylcholine depamine and serotonin. Nerves transfer message through them.
Question 21.
Write the structure of one neurotransmitter.
Answer:
Question 22.
Why do drugs cause side effects?
Answer:
Side effects are caused when a drug binds to more than one type of receptor.
Question 23.
Name one non-narcotic and one narcotic drug.
Answer:
Non-narcotic: Aspirin or paracetamol.
Narcotic: Morphine and many of its homologues.
Question 24.
Name one antimicrobial. Give its structure.
Answer:
Question 25.
How do the antimicrobials control the microbial disease?
Answer:
- It kills the organism in the body.
- It inhibits or arrests the growth of the organisms.
- It increases immunity and resistance to infection of body.
Question 26.
Penicillin itself has a narrow spectrum. Name any two modifications of penicillin.
Answer:
Ampicillin and amoxicillin are modifications.
Question 27.
Chloramphenicol is a broad-spectrum antibiotic. Why is it so and what are the diseases for which it is given. ‘
Answer:
Chloramphenicol is rapidly absorbed from the gastrointestinal tract and hence can be given orally in case of typhoid, dysentery, acute fever, certain forms of urinary infections meningitis and pneumonia.
Question 28.
Name two compounds present in birth control pills.
Answer:
Birth control pills essentially contain a mixture of two harmonies: Synthetic estrogen and progesterone derivatives.
Question 29.
Name one antifertility drug.
Answer:
Norethindrone.
Question 30.
Give the name and structure of one class II preservative.
Answer:
Sodium benzoate (C6H5COONa).
Short Answer Type Questions
Question 1.
Name an alkaloid in each case used for the treatment of (i) hypertension, (ii) malaria fever, (iii) pain.
Answer:
- Reserpine is the alkaloid used for treatment of hypertension.
- Quinine is the alkaloid used for treatment of malaria.
- Morphine is the alkaloid used for the treatment of pain.
Question 2.
Name the active chemotherapeutic agent in each of the following used medicines: (i) Brufen, (ii) Crocin, (iii) Disprin.
Answer:
- Brufen: p-Isobutylphenyl-2-propanoic acid.
- Crocin: Paracetamol,
- Disprin: Acetylsalicylic acid.
Question 3.
What is an antibiotic? Give the name of first antibiotic discovered.
Answer:
Antibiotics are chemical substances (produced wholly or partially by chemical synthesis) which in low concentration, either kill or inhibit the growth of microorganisms by intervening in their metabolic process. Penicillin was the first antibiotics discovered.
Question 4.
What led the scientists to discover that there is relationship between the structure and activity of antimicrobials. Illustrate with an example.
Answer:
Body tissues are coloured by dyes selectively. One such dye is an azo dye having the linking -N= N-(azo group). Search began for the compounds resembling the structure of azo dyes and selectively binding to bacteria. The first effective antibacterial agent prontosil was thus prepared.
Question 5.
How do the antimicrobials control the microbial diseases?
Answer:
Antimicrobials control the microbial diseases in three ways:
- Bactericidal drugs kill the organism in the body.
- Bacteriostatic drugs inhibit or arrest the growth of organism.
- Antimicrobials increase immunity and resistance to infection of the body.
Question 6.
What do you mean from the words: (i) Chemotherapy, (ii) Target molecules, (iii) Lead compounds.
Answer:
- Chemotherapy-Use of chemicals for therapeutic effect is called chemotherapy.
- Target molecules-Drugs usually react with biological macromolecules such as carbohydrates, proteins, lipids and nucleic acids. These are called target molecules.
- Natural or synthetic compounds from the drugs are designed and are called lead compounds. Drugs are designed from lead compounds to interact with specific targets to minimise side effects.
Question 7.
Why are detergents preferred to soaps. How are detergents classified?
Answer:
Detergents are preferred to soaps because they work even in hard water as cleansing agents. Detergents are classified in the three categories:
- Anionic detergents,
- Cationic detergents,
- Non-ionic detergents.
Question 8.
How do drugs interact with enzymes?
Answer:
Drugs inhibit the activites of enzymes. Such drugs are also called enzyme inhibitors. Enzyme inhibitors can block the binding site and prevent the binding of substrate or these can inhibit the catalytical activity of enzyme.
Long Answer Type Questions
Question 1.
What are detergents? Give their scheme of classification. Explain. Why are detergents preferred over soaps?
Answer:
Detergents: As a result of high dissolving power, the naturally occurring water always contains dissolved materials, particularly ionic substances. Hard water Contains certain metal ions, such as Ca2+ and Mg2+. These ions react with soap, (sodium salts of stearic and similar organic acids), to produce a curdy precipitate of calcium and magnesium salts. This precipitate adheres to clothing and blocks the ability of soaps to remove oil and grease from fabrics. Synthetic detergents are very similar to the salts of fatty acids found in soap, except that they are manufactured chemically from materials others than animal fats. Examples includes salts called sodium alkylbenzenesulphonates, which have the general structure.
Why are detergents preferred over soaps?
Their advantage over natural soaps is that they work in had water. The anions of synthetic detergents don’t precipitate in the presence of Ca2+/Mg2 so their cleansing action is not affected by hard water.
Types of Detergents
Detergents are mainly classified into three categories namely anionic, cationic and non-ionic. Long .chain alcohols are used in the manufacture of some of the synthetic anionic detergents. The long-chain alcohols are treated with concentrated sulphuric acid to form alkyl hydrgen sulphates of high molecular mass and finally the alkyl sulphates are neutralized with alkali to form salts.
A detergent of the above type is an anionic detergent, named so as a large part of the molecule is an anion. The single anionic detergent in largest use today in household detergents is alkylbenzene-sulphonate.
1. The anionic detergents are also effective in slightly acidic solution to form an alkyl hydrogen sulphate which is a soluble material, whereas the soaps react with the acidic solutions to form insoluble fatty acids.
2. A second type of detergents is the cationic detergents. These are mostly acetates or chlorides of quaternary amines. Being more expensive than the anionic detergents they find limited uses. Such detergents however, possess germicidal properties and are used quite extensively j as germicides. Cetyltrimethylammonium chloride, is an example.
3. Some of the detergents are nonionic, like the esters of high molecular mass formed by reactions between polyethylene glycol and stearic acid.
Question 2.
(i) What are antacids? List some of the compounds which 1 -are used, as antacids.
(ii) Giving examples, explain the following.
(a) Tranquilizers, (b) Antifertility drugs, (c) Antihistamines
Answer:
(i) Substances which remove the excess acid and raise the pH to appropriate level in stomach are called antacids. Magnesium hydroxide [Mg(OH)2], Magnesium carbonate [Mg CO3], Magnesium Disilicate, Al (OH)3 gel, NaHCO3 and AlPO4 are commonly used antacids.
(ii)
(a) Tranquilizers are a class of chemical compounds used for the treatment of stress, mild and severe mental diseases. These are used to relieve stress, fatigue by inducing a sense of well-being. They form an essential component of sleeping pills. They include derivatives of barbituric acid viz., Veronal, Luminal seconal. These derivatives are called bartbiturates- which are hypnotics – sleep producing agents. Equanil is used in controlling depression and hypertension.
(b) Antifertility drugs are the drugs used to control birth. These are oral contraceptics which are natural products known as STEROIDS. Steroids are the active ingredients of the pill functioning as on antifertibility drug. It controls the female menstrual cycle and ovulation. The birth control pill is essentially a mixture of synthetic estrogen and progesterone derivatives, which are more potent than the natural harmones. Some of the commonly used pills contain a combination of norethindrone and ethynyl estradiol. Mifepristone is a synthetic steroid that blocks the effect of progesterone and is used as a “morning-after pill”.
(c) Antihistamines-These are the drugs used to treat allergy and are called anti-allergical drugs. Since the allergic reactions like skin rashes are caused due to liberation of histamine in the body, that is why these drugs are called antihistamines. Other than skin rashes, these drugs are useful for conjunctivitis (inflammation of conjunctiva of eye) and rhinitis (inflammation of nasal mucosa) in seasonal rhinitis and conjunctivitis, these drugs relieve sneezing, nasal discharge and itching of eyes, nose and throat. Common drugs of this group are diphenhydramine, chlorpheniramine and promethazine.