CBSE Class 12 Chemistry Revision Notes Chapter 16

Class 12 Chemistry Chapter 16 Notes: Chemistry in Everyday Life 

The 16th Chapter of Chemistry in Class 12 deals with Chemistry that we experience in everyday life. , and the Class 12 Chemistry Chapter 16 Notes will further explain the  science surrounding it. . 

Furthermore, it will help you to understand the role of Chemistry in little things which usually go unnoticed.  Besides that, you see that every branch of science is helpful in various aspects of our lives. However, this particular chapter focuses solely on  Chemistry. Thus, Class 12 Chemistry Chapter 16 Notes will come  handy in studying the same.

Moreover, you will learn about the various chemicals that are present in  food that we consume. It will explain its  impact on human health. It sheds light on the various cleansing agents and the chemicals present in them. Furthermore, Chemistry Chapter 16 Class 12 Notes also covers the information about drugs, their Classification, and its  impact on our lives.

• The Class 12 Chemistry Chapter 16 Notes also explains the Chapter’s main chemical equations and  formulas. 
• The mechanism of drugs working on the human body is also explained in the CBSE Class 12 Chemistry Chapter 16 Notes. 
• Various solved examples related to the above mentioned topics are also covered in Chemistry in everyday life Class 12 Notes. 
• Students can quickly access all the l topics from  Class 12 Chemistry Chapter 16 Notes  available on Extramarks website. 

Key Topics Covered in Class 12 Chemistry Chapter 16 Notes

In this Chapter, we shall learn the application of Chemistry in three crucial and exciting areas, namely medicines, food products, and cleaning agents. For cleanliness, we use soap, detergents, toothpaste, bleaches, etc. These all are chemical compounds.

Similarly, clothes(silk, wool, cotton, terylene), food materials(carbohydrates, proteins, oils, fats), medicines(antibiotics, antimalarial, etc.),  explosives, fuel, rocket propellants, building materials, etc. are all chemical compounds or derived from them.

Drugs and their Classification:

As stated in the Class 12 Chemistry Chapter 16 Notes,  drugs are chemicals of low molecular weights (～100～500u). They produce biological responses by interacting with macromolecular targets. These chemicals are called medicines if the natural reaction is therapeutic and valuable. They are used in the diagnosis, prevention, and treatment of diseases. 

A drug of the same type can be Classified into four categories. Let us study these four categories in detail.

1. Based on Pharmacological Effects:

Pharmacology is the field of science that studies drugs and their reactions in the human body. A drug occurs with a pharmacological effect, i.e., the effects of a drug on the human body. This effect will heal what is ailing the body and have a positive biological response. It is helpful for doctors because it provides them with various drugs available to treat particular problems. So they are Classified based on what kind of effect they have on the body. For Example,

• Analgesics relieve the body from pain or show a painkilling effect.
• An antibiotic drug will cure infections.
• Antiseptics will kill or arrest the growth of germs and microorganisms.

So any drug in the same category can have many compositions, dosages, and brand names. But the net effect will be the same.

2. Based on Drug Action:

This Classification as written in Class 12 Chemistry Chapter 16 Notes, is based on which biochemical process the drug targets in the body. A biochemical process is the complex chemical reactions that occur inside the human body to keep it functioning normally, as the production of enzymes is a biochemical process.

Now drugs will be classified according to their targets. For Example, antihistamines are taken to block the production of histamines so that swellings and allergies can be controlled. So no matter which antihistamine drug you take, their main aim will be to target and reduce the production of the histamines in your body.

3. Based on Chemical Structure:

The drug is based on its chemical structure. It is seen that drugs with a similar molecular structure have the same pharmacological effects and drug actions. The slight variation in their structures gives them different potential. But the basic skeleton of their structure remains the same. So this is yet another way  to  classify a drug. Sulphonamides have standard structural features, as shown below.

4. Based on Molecular Targets:

This Classification is based on the macromolecule with which the drugs interact with the target. The drug targets can be carbohydrates, lipids, proteins, nucleic acids, or any other biomolecule. The drugs with similar structures have similar reactions with such biomolecules. 

Drug Target Interaction:

Macromolecules of biological origin perform several functions in the human body. For Example, proteins that act as biological catalysts in the body are called enzymes. They are crucial to the communication system in the body and are known as receptors. Carrier proteins move polar molecules across the cell membrane, and nucleic acids have coded genetic information for the cell.

Enzyme as drug targets:

1. Catalytic action of Enzymes: 

To carry catalytic activity, enzymes perform two significant functions:

1. The first primary function of an enzyme is to grip the substrate for a chemical reaction. Active sites of enzymes pick the substrate molecule in a suitable position so that it can be attacked by the reagent effectively. The substrates can bind to the enzyme’s active site through ionic bonding, van der Waals interaction, hydrogen bonding, or dipole-dipole interaction.

1. The second primary function of an enzyme is to give functional groups which will attack the substrate & carry out a chemical reaction.
2. Drug-Enzyme Interaction: 

These drugs block the enzyme’s binding site, prevent substrate binding, or inhibit the enzyme’s catalytic activity. Such drugs are called enzyme inhibitors. Drugs inhibit the addition of substrate on the active site of enzymes in two ways:

1. Some drugs compete with the natural substrate for their addition to the active sites of enzymes. Such drugs are known as competitive inhibitors.
2. Few drugs do not bind to the enzyme’s active site. These bind to a different site of an enzyme, which is called an allosteric site. This inhibitor binding at the allosteric site modifies the shape of the active site in such a way; therefore, the substrate can’t recognise it.

Important Note: If the bond formed between an enzyme and an inhibitor is a strong covalent bond and cannot be broken easily, the enzyme is blocked permanently. The body then decays the enzyme-inhibitor complex and synthesises the new enzyme.

3. Drug-Target Interaction as Receptors:

Receptors are proteins that are important to the body’s communication process. Protein receptors are embedded in the cell membrane in such a way that their tiny part possessing active site projects out of the membrane surface & opens on the outer region of the cell membrane.

In the body, a message between two neurons and that between neurons of muscles is transmitted through certain chemicals. These chemicals are termed chemical messengers and are received at the binding sites of receptor proteins. To accommodate a messenger, the shape of the receptor site changes, and as a result, the message transfer happens into the cell. Thus, a chemical messenger gives a message to the cell without entering the cell.

Note: There are a large number of different receptors in the body that interact with various chemical messengers. These receptors exhibit selectivity for one chemical messenger over the other because their binding sites have different shapes, structures, and amino acid compositions.

Agonists:

Drugs that bind to the receptor site and inhibit its natural function are antagonists. These are useful when blocking a message is required. Other drugs mimic the genuine messenger by switching on the receptor agonists. These are useful when there is a lack of natural chemical messengers.

 Agonists can be understood more clearly if read and learned from Class 12 Chemistry Chapter 16 Notes. Students are recommended to visit the Extramarks website and access them.

Therapeutic Action of Different Classes of Drugs:

A few important classes of drugs are:

1. Antacids: 

Antacids are the chemical substances that neutralise the excess acid in gastric juice and raise pH to a suitable level in the abdomen. For Example, Baking soda, a mixture of Aluminium and Magnesium hydroxide, is commonly used as antacids. 

• Usually, liquid antacids are more effective than tablets because of the more surface area available for interaction and neutralisation of acids. 
• Milk is a weak antacid. The stomach will become more alkaline by using excess hydrogen carbonate, producing more acid. So metal hydroxides are applied instead, which are insoluble and do not enhance the pH level. But they will only cure the symptoms, not the cause. 
• A breakthrough in the treatment of hyperacidity happened with the discovery of a chemical known as histamine that stimulates the secretion of pepsin and hydrochloric acid in the abdomen. 
• The drug cimetidine (Tagamet) was designed to prevent the reaction of histamine with the receptors present in the abdominal wall. This resulted in the release of a few amounts of acid. 
• The importance of the drugs was so much that it remained the most effective selling drug in all countries until another drug, ranitidine (Zantac), was discovered.

2. Antihistamine: 

Histamine is a potent vasodilator. It has several functions. It contracts the soft muscles in the bronchi and gut & relaxes other muscles, such as those in the walls of thin blood vessels. 

• Histamine is also behind the nasal congestion included with the common cold and allergic response to pollen. 
• Synthetic drugs, brompheniramine (Dimetapp) and terfenadine (Seldane), are shown as antihistamines. They obstruct the natural action of histamine by competing with histamine for binding sites of receptors where histamine exerts its effect. 
• The antihistamines don’t affect the acid secretion in the stomach because antiallergic and antacid drugs work on different receptors.

3. Neurologically Active Drugs:

Tranquilizers  and analgesics are neurologically active drugs. These affect the message transmit mechanism from the nerve to the receptor.

• Tranquilizers are chemical compounds used to treat stress and mild or even severe mental diseases. They develop an essential component of sleeping pills. These relieve anxiety, irritability, stress, or excitement by inducing a sense of well-being.
• There are various types of tranquilisers. They function by different mechanisms. For Example, noradrenaline is one neurotransmitter that plays a role in a mood swing. When the level of noradrenaline is low, the signal-sending activity becomes low, and the person suffers from depression. In such situations, antidepressant drugs are required. These medicines inhibit the enzymes that catalyse the degradation of noradrenaline.

• If the enzyme is inhibited, this vital neurotransmitter is slowly metabolised and can activate its receptor for extended periods, thus counteracting the effect of depression. Iproniazid and phenelzine are two such drugs. 
• Few tranquilisers, namely chlordiazepoxide and meprobamate, are relatively mild tranquilisers suitable for relieving tension. 
• Equanil is applied in controlling depression and hypertension.

• A few introductory tranquilisers Classes are Derivatives of barbituric acid viz., veronal, Amytal, Nembutal, luminal and seconal. These derivatives are called barbiturates. They are hypnotic, i.e., sleep-producing agents.
• Some other substances used as tranquilisers are valium and serotonin.

4. Analgesics: 

They reduce or abolish the pain without causing impairment of consciousness, mental confusion, incoordination or paralysis, or other nervous system disturbances. These are Classified as follows:

•  Non-narcotic (non-addictive) analgesics.
• Narcotic drugs 

1. Non-narcotic (non-addictive) analgesics: 

Aspirin and paracetamol belong to non-narcotic analgesics. Aspirin is the most simple example. It inhibits the preparation of chemicals known as prostaglandins that stimulate inflammation in the tissue and cause pain. These medicines are effective in relieving skeletal pain such as that due to arthritis. These medicines have many other effects, such as reducing fever (antipyretic) and preventing platelet coagulation. They stop platelet coagulation because of this anti-blood clotting action. Aspirin is used to avoid heart attacks. Aspirin is toxic to the liver and sometimes causes bleeding from the stomach. So naproxen, ibuprofen, and paracetamol are broadly used analgesics.

1. Narcotic Analgesics:

Morphine and its homologues like heroin, codeine, etc., when administered in medicinal doses, relieve pain and produce sleep. These poisonous doses have stupor, coma, convulsions, and ultimately, death. Morphine narcotics are sometimes called opiates since they occur from the opium poppy. These analgesics are mainly used to relieve postoperative pain, cardiac pain and pain of terminal cancer, and childbirth. 

5. Antimicrobials: 

Antimicrobial drugs destroy or block the development or inhibit the pathogenic action of microbes. 

• These  antibacterial drugs are used to deal with concerns related to bacteria. 
• These drugs are used to deal with fungi, and  antiviral medicines are used to deal with viruses. 
• Antiparasitic medicines are used to deal with parasites.

6. Antibiotics:

These are less toxic for humans & animals.  They are used as drugs to cure infections.

• Antibiotics are substances developed partly or wholly by the chemical synthesis process. 
• Antibiotics intervene in the metabolic reaction by inhibiting the growth of microorganisms or destroying microorganisms.
• Scientist Paul Ehrlich produced the medicine arsphenamine, known as salvarsan, for syphilis & got the Nobel prize for Medicine in 1908. In 1932. He developed prontosil as well.
• The primary  example of antibiotics is Penicillin, a highly effective  medicine for pneumonia, Bronchitis, abscesses, sore throat, etc. 
• Synthetic antibiotics Streptomycin is applied for the treatment of (Tuberculosis), Chloromycetin – (Typhoid, Meningitis, Pneumonia, diarrhoea, dysentery, etc.). Tetracycline – (Acute fever, trachoma, dysentery & urinary tract infection).

7. Antiseptics and disinfectants:

They are chemicals that either kill or prevent the growth of microorganisms.

8. Antiseptics:

These are applied to living tissues like wounds, cuts, ulcers, and diseased skin surfaces. They are not ingested like antibiotics. Examples are soframycin, furacine, and Dettol (a mixture of chloroxylenol & terpineol). 

• Bithionol is added to soap to impact antiseptic properties, tincture of iodine(Iodine which is a powerful antiseptic, is a 2-3 % solution in the alcohol-water mixture), Boric acid in dilute aqueous solution, and iodoform, which is also used as antiseptic for wounds.

9. Disinfectants: 

They are applied to surfaces of inanimate objects such as floors, instruments, drainage systems, etc. The same substances can act as antiseptics and disinfectants by varying the concentration. For Example – a 0.2% solution of phenol is an antiseptic, but a 1 % solution of phenol is a disinfectant.

10. Antifertility Drugs: 

They are used in the direction of birth control and family planning. Birth control pills essentially suppress a mixture of synthetic estrogen & progesterone derivatives. Both of these compounds are hormones. 

• Progesterone hormones contain ovulation. 
• Synthetic progesterone derivatives are more strong than progesterone. For example – Norethindrone (a synthetic progesterone derivative, as antifertility action), ethynylestradiol/Novestrol (synthetic estrogen). 

Students may refer to NCERT Class 12 Chemistry Chapter 16 Notes for information on various Classes of Drugs.

Chemicals in food:

Chemicals are combined with food for the following reasons:

• Their preservation.
• Enhancing their appeal.
• Adding nutritional value to them. 

The main categories of food additives are as follows:

1. Food colours.
2. Flavours and sweeteners sucrose (Natural sugar).
3. Fat emulsifiers and stabilising agents.
4. Preservatives (Nutritional supplements like minerals, vitamins, & amino acids).
5. Flour improvers – antistaling agents & bleaches.
6. Antioxidants.
7.  Vitamins, minerals,  and amino acids are nutritional supplements. 

Artificial Sweetening Agents:

Sucrose and fructose are the most broadly used natural sweeteners. But their intake increases calories in the diet, and an excess of them can cause tooth decay. Ortho-sulphobenzimide, also termed saccharin, is the first famous artificial sweetening agent, which is about 550 times as sweet as cane sugar. It appears  to be entirely inert and safe when taken. Its use is of great value to sugar persons and people who need to control their calorie intake. A few essential artificial sweetening agents are given below.

1. Aspartame: It is the most successful and widely  used sweetener. It is usually  100 times as sweet as sugar cane . It is a methyl ester of dipeptide prepared from aspartic acid and phenylalanine. 
2. Sucralose: It is a trichloro derivative of sucrose. Its appearance and taste are like sugar. 

Food Preservatives:

They prevent the spoilage of food due to microbial growth. Commonly used preservatives are  salt, sugar, vegetable oils, sodium benzoate(C6H5COONa), salts of sorbic acid, and propanoic acid to prevent food spoilage due to microbial growth. Sodium benzoate is used in finite quantities and is metabolised in the body.

Students may refer to Class 12 Chemistry Chapter 16 Notes for a more detailed explanation of food preservatives.

Cleansing Agents:

They improve the cleansing properties of water and help remove fats that bind other materials to the fabric or skin. Soaps contain sodium or potassium salts of long-chain fatty acids applied for cleaning. Example – oleic, stearic & palmitic acids. Soaps are formed by saponification, which involves heating fat(glycerol esters of fatty acids) with an aqueous sodium hydroxide solution.

In this chemical reaction, esters of fatty acids are hydrolysed, and the soap obtained remains in colloidal form. It is residue from the solution by adding sodium chloride(NaCl). The solution left after separating soap contains glycerol and can be restored by fractional distillation.

Types of Soaps:

• Toilet soaps: They are formed by using better grades of fats and oils, and care is taken to remove excess alkali. Colour, design and perfumes are mixed to make these more attractive. 
• Soaps that float in water: Soaps that float in water are made by beating tiny air bubbles before their hardening.
• Transparent soaps: These are synthesised by dissolving the soap in ethanol and evaporating the excess solvent.
• Medicated soaps: In this type of soap, substances of medicinal value are added.
• Shaving soaps: Shaving soaps contain glycerol to prevent rapid drying. A gum called rosin is mixed while making them. It prepares sodium rosinate, which lathers well.
• Laundry soaps: This soap contains fillers like sodium rosinate, sodium silicate, borax, and sodium carbonate.
• Soap granules: They are dried miniature soap bubbles.
• Soap powders and scouring soaps contain soap, a scouring agent (abrasive) such as powdered pumice or finely divided sand, and builders such as sodium carbonate and trisodium phosphate.
• Soap Chips: Soap chips are made by running a thin sheet of melted soap onto a superb cylinder and scraping off the soaps in small broken pieces.

Soaps do not work in hard water. Why? 

Generally, hard water contains calcium and magnesium ions, and soaps do not work in hard water because of the presence of calcium and magnesium ions which form insoluble salts with soaps that separate as scum in water.

The scum now separated hinders soap action as the residue adheres to the fabric as a gummy mass. Also, the hair washed with water looks dull because of this sticky residue. 

Synthetic Detergents: 

Synthetic detergents are cleansing agents with soap’s properties but do not contain any soap. 

• These can be used in soft and hard water, giving foam even in hard water. 
• Calcium & magnesium salts are also detergents as sodium salts are also soluble in water. 
• Some of the detergents offer foam, even in ice-cold water. 
• The straight-chain alkyl group contains biodegradable detergents, whereas the branched alkyl group containing detergents is non-biodegradable.

Synthetic detergents are classified into three categories:

• Anionic detergents.
• Cationic detergents.
• Non-ionic detergents.

1. Anionic detergents:

These are sodium salts of sulphonated long-chain alcohols or hydrocarbons. Alkyl hydrogen sulphates formed by treating long-chain alcohols with concentrated sulphuric acid are neutralised with alkali to form anionic detergents. Similarly, alkyl benzene sulphonates are obtained by neutralising alkyl benzene sulphonic acids interacting with alkali. In anionic detergents, the anionic factor of the molecule is responsible for the cleansing action.

Sodium salts of alkyl benzene sulphonates are an essential class of anionic detergents. They are mainly used for household work. Anionic detergents are also used in toothpaste.

2. Cationic detergent:

It is quaternary ammonium salts of amines with acetates, chlorides, or bromides as anions. The cationic part possesses a long hydrocarbon chain and a positive charge on the nitrogen atom. Hence, these are known as cationic detergents. Cetyltrimethylammonium bromide is a leading cationic detergent and is used in hair conditioners. Cationic detergents have germicidal characteristics and are expensive; therefore, these are of limited use.

3. Non-ionic Detergents: 

Non-ionic detergents do not accommodate any ion in their constitution. Such detergent is developed when stearic acid interacts with polyethene glycol. Liquid dishwashing detergents are non-ionic types. This type of detergent’s mechanism of cleansing action is similar to that of soaps. These also vanish in grease and oil by micelle formation. The main problem in using detergents is that bacteria cannot degrade quickly if their hydrocarbon chain is highly branched.

Advantages of Synthetic detergents over Soaps:

1. Detergents can be used with hard water, which soap cannot do.
2. They can be used in an acidic medium, unlike soaps.
3. They are more soluble in water.
4. They have more decisive cleaning action than soaps.

Students may refer to various study materials based on CBSE solutions Class 12 Chemistry Chapter 16 Notes to ace their examinations,  available at the Extramarks website. 

CBSE solutions Class 12 Chemistry Chapter 16 Notes: Exercises &  Solutions

The CBSE solutions Class 12 Chemistry Chapter 16 Notes exercises and solutions are based on NCERT books. Every exercise is compiled to add more value to the chapter. Students may refer to various study materials such as revision notes,  past years questions papers, and essential questions and learn more about NCERT and CBSE Syllabus available on Extramarks website. 

The key topics which students might find challenging while studying have been prepared in such a way that they can understand and get to the point answers without wasting much time on a single subject.

Extramarks faculty experts completely understand what is legitimate as per the board’s standards have  explained CBSE solutions of  Class 12 Chemistry Chapter 16 Notes in detail. In addition to Chapter 16, students can access CBSE Solution for the rest of the  Chemistry chapters of Class 12 by registering themselves on the Extramarks website. 

Students can refer to the respective exercise links above to access the NCERT solutions Class 12 Chemistry Chapter 16 Notes. Students can also explore a repository  of educational content available  on the Extramarks website.

Click on the respective links below  to access NCERT Solutions for all classes from 1 to 12: 

NCERT Exemplar Class 12 Chemistry

All solutions and problems in NCERT Exemplars are provided to help students prepare for their final examinations. These exemplar questions are a little more complex and cover every topic  in Class 12 Chemistry.

Students will fully understand the concepts covered in each chapter by practising this NCERT Exemplar for Chemistry Class 12. 

The list of additional study materials available for students are given below:    

Exemplars provide the best solutions to challenges that students face in higher classes, whether it’s getting advanced level questions for further practice, assignments,  worksheets to test their knowledge and understanding, is ideal for every student irrespective of their level. Needless to say, these questions strictly follow updated 2021-22 CBSE guidelines.

Key Features of CBSE Solutions Class 12 Chemistry Chapter 16 Notes

The main topics covered in Class 12 Chemistry Chapter 16 Notes are Drugs and Classification of drugs, Drug-target interaction, Therapeutic Action of various Classes of Drugs, Chemicals in Food, Cleansing Agents & Everything related to general everyday Chemistry. CBSE Class 12 Chemistry Chapter 16 Notes also include a brief introduction to critical day-to-day substances like Tranquilisers, Analgesics, Antimicrobials, and Antibiotics. Antiseptics and Antifertility  Drugs, disinfectants, etc. 

Chemistry in Everyday life is important from the examination point of view, especially  for  examinations like IIT, JEE, and NEET. Hence, while studying Chemistry, the best quality Notes and solutions provided by Extramarks  are  extremely useful   for students planning to take competitive exams after high school.

Key Features of CBSE Solutions Class 12 Chemistry Chapter 16 Notes are: :

• Straightforward language and eye-catching format.
•  Experienced subject matter experts  have created several pointwise notes that help students conveniently recall the crucial points in the exam and use these solutions for last-minute revisions
• These advanced Notes include a detailed explanation  to enable a smooth and deep learning experience so that students need not look elsewhere to supplement their studies to better their performance.  
• They can be used to study right after school or revise Notes during Examinations. It will  help them to understand the important points easily and make them revise quickly. The more you practice, the easier it will get.
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