Ch 16Chemistry in Everyday Life — Class 11 Chemistry, concept-first.

Chemistry is not confined to the laboratory -- it runs through the whole history of the Earth and of life on it.

Food is the body's source of nutrients, which serve two broad purposes: some are burned as fuel to supply energy, and others regulate growth and maintain or repair body tissues.

Beyond simply supplying nutrients, food also has a 'quality' that changes over time, and that quality is judged by several practical parameters: flavour, smell, texture, colour, and the extent of micr…

One of the most familiar examples of food-quality change is the browning of a cut fruit or vegetable -- a banana, an apple, a potato, a bottle gourd -- within minutes of being peeled or sliced.

Rancidity is the general name for the unpleasant smell and disagreeable taste that develops in oils and fats after they have been kept for a long time, and the chapter identifies two distinct chemical…

The distinction between saturated and unsaturated fats comes down to molecular shape and how closely the fat molecules can pack together.

Within the broader category of unsaturated fats, two specific families attract particular attention because of their health effects: fatty acids containing an omega-3 double bond and fatty acids conta…

An antioxidant, in the context of food chemistry, is a substance that delays the onset of oxidation or slows its rate once it has begun, and food manufacturers use antioxidants specifically to extend…

A drug, in the pharmacological sense used throughout this section, is any chemical that interacts with the body's biomolecules -- carbohydrates, lipids, proteins or nucleic acids -- and, through that…

Analgesics are drugs that relieve pain -- the name comes from the Greek word 'algesis', meaning a feeling of pain -- and roughly half of all analgesics work specifically as anti-inflammatory drugs, re…

Antimicrobial is the umbrella term the chapter uses for any drug that inhibits or kills microbial cells -- a category spanning bacteria, fungi and viruses.

Among commonly used antiseptics, the chapter names inorganic examples -- iodine and boric acid -- alongside organic examples such as iodoform and a family of phenolic compounds.

The chapter's antibiotic case studies form a connected historical narrative. Arsenic compounds had long been known to be highly poisonous to humans; the German bacteriologist Paul Ehrlich deliberately…

Traditional medicine, developed and refined over centuries of observation and use, is an increasingly important starting point for modern drug discovery -- the chapter notes that Indian medicinal trad…

Cleansing agents are, in the most general sense, substances used to remove stain, dirt or clutter from a surface, and they fall into two broad categories: those that occur naturally (soaps) and those…

Commercially, cleansing agents fall into two types based on their chemical composition: soaps and synthetic detergents.

Soaps and synthetic detergents clean dirty, greasy surfaces by exactly the same underlying mechanism, even though their chemical structures differ.