Importance of Chemistry in Daily Life

CHEMISTRY INTRODUCTION TO CHEMISTRY

Chemistry is the branch of science which deals with substances—their composition, properties and their interaction with other substances.

Importance

Chemistry

MEDICINE AGRICULTURE INDUSTRIES o o o Drugs Pesticides Dyes and paints o Antibiotics o Insecticides o Plastics

o Fertilisers o Synthetic fibres

o Petrochemicals

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CHEMISTRY INTRODUCTION TO CHEMISTRY

Discoveries in Ancient Times

Metals: Metals were developed and were used to make vessels and other equipment.

Yeasts: Yeasts were used in wine fermentation.

Salt: Salt was used as a food preservative.

Glass: Glass was formed by fusing sand, soda and clay; it was used for various purposes.

Plant extracts: Plant extracts were used for dyeing and colouring clothes.

Chemists and their Discoveries

Period Scientist Discovery 8th century Alchemists Nitric acid was named aqua fortis. 9th century - Sulphuric acid was first mentioned. 1630 Van Helmont Carbon dioxide was discovered. 1772 Daniel Rutherford Nitrogen gas was discovered. 1774 Joseph Priestly Oxygen and ammonia were discovered. 1776 Henry Cavendish Hydrogen gas was first prepared. 1776 De Lassone Carbon monoxide was first prepared. 1777 Lavoisier The elementary nature of sulphur was recognised. 1807 John Dalton Atomic theory was postulated. 19th century - Modern theory was established.

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CHEMISTRY INTRODUCTION TO CHEMISTRY

Branches of Chemistry

Inorganic Chemistry Organic Chemistry Study of elements and Study of carbon and its compounds compounds

Branches of Chemistry Biochemistry Physical Chemistry Study of chemical Study of physical aspects processes in living matter of chemistry

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CHEMISTRY INTRODUCTION TO CHEMISTRY

Chemistry Laboratory

A chemistry laboratory is a place where experiments involving different chemical reactions are carried out.

A chemistry laboratory is equipped with a large variety of laboratory apparatus.

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CHEMISTRY INTRODUCTION TO CHEMISTRY

Apparatus Used in a Chemistry Laboratory

Apparatus Description  A special glass tube with one open and one closed end. This test tube is made of Pyrex glass to withstand strong heat.  It is used for heating, preparing gases, identifying gases and conducting chemical reactions.

Test Tube  A test tube holder is made of a metallic clamp fixed to a wooden handle.  It is used for holding a test tube during heating or chemical addition. Test Tube Holder

 A glass container with a lid. Beakers are available in different sizes.  It is used for holding, pouring and mixing solutions.

Beaker  It is made of glass and is available in various sizes.  It is used for pouring liquids from one vessel into the other.  It is used in the filtration process to transfer liquid.

Funnel

Round Bottom Flat Bottom  A round bottom flask is used in gas Flask Flask preparation experiments where heating is required.  A flat bottom flask is used in gas preparation experiments where heating is not required.  A conical flask is used for storing and mixing liquids.

Conical Flask

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CHEMISTRY INTRODUCTION TO CHEMISTRY

 A graduated cylinder made of glass.  It is used for measuring liquids.

Measuring Cylinder  A dish made of porcelain or borosilicate glass to withstand strong heating.  It is used in experiments involving strong heating.

Evaporating Dish

 An iron rod with a clamp, which can be rotated and raised, placed on a rectangular heavy iron base.  It can be used for holding apparatus during chemical reactions.

Retort Stand  An equilateral iron triangle mounted on three iron legs for support.  It supports all the glass apparatus and wire gauze placed on it.

Tripod Stand  A rectangular wire mesh with asbestos at its centre.  It prevents the cracking of glass apparatus during heating.  It also helps in uniform distribution of heat.

Wire Gauze  A long metal tube with one end used for burning and the other end connected to the gas supply. It consists of 4 parts—a base, nozzle, tube and air hole.  It is used for heating purposes.

Bunsen Burner

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CHEMISTRY INTRODUCTION TO CHEMISTRY

 It is made of glass and is cylindrical in shape.  It is used for collecting gases and holding them in captivity.

Glass Jar  It is a wooden or plastic stand with holes and upright pegs.

Test Tube Stand

 It contains an iron rod with a clamp, which can be rotated and raised, placed on a rectangular heavy iron base.  It can be used for holding apparatus during chemical reactions.

Retort Stand

 It consists of a glass pot filled with spirit and a neck with a hole. A cotton wick soaked in spirit passes through the hole.  It is used for heating purposes.

Spirit Lamp

 It consists of a long glass tube with a broad inlet at the top. Its lower end is dipped below the solution in the flask.  It allows the entry of reactants into the round bottom flask.

Thistle Funnel

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CHEMISTRY INTRODUCTION TO CHEMISTRY

 It is a thin hollow glass tube of various shapes.  It is used for the transfer of gases from one apparatus to the other.  It is also used for connecting one piece of gas apparatus to the other.

Delivery Tube  It is a clay vessel with two outlets.  It is used in collecting gases by the downward displacement of gases.

Beehive Shelf  It is a long glass jar which is closed at one end and open at the other end.  It is used for various experiments which involve the collection of gases by the downward displacement of water, the downward displacement of air and the upward displacement of air.

Gas Jar  It is a calibrated glass tube with openings at both ends.  It is used to transfer or measure small quantities of liquid.

Pipette  It is a uniform-bore glass tube with fine graduations and a tap at the bottom.  It is used for accurate fluid dispensing and measurement.

Burette