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Questions 1.Fill in the blanks: (a)1 lakh = _______________ ten thousand (b)1 million = _______________ hundred thousand (c)1 crore = _______________ ten lakh (d)1 crore = _______________ million (e)1 million = _______________ lakh Answetr 1.(a) 10(b) 10 (c) 10(d) 10 (e) 10

BRANCHES OF CHEMISTRY There are several branches of chemistry. Inorganic chemistry is the study of elements and compounds that are found in non-living material. Organic chemistry is the study of carbon compounds. Many of them are found in living things. Physical chemistry studies how physical properties, such as heat and pressure, affect chemical reactions. Biochemistry studies the chemical make up and behaviour in living things. Economic Importance of Chemistry : The progress in modern society is indeed based on advances in chemistry. Thus, some of the most essential needs for the living of humans require the use of various chemical compounds. These include fertilizers, insecticides, antibiotics, building material, etc.

Beaker : It is a cylindrical vessel with a flat bottom and a pouring tip. The beaker is used for mixing, storing and heating substances.

Start off your program by giving some basic information about what participants can expect to learn. Introduce the topic and provide a basic outline of what's to come using videos, images, and text.

1. It is advisable to wear a laboratory coat or an apron to protect the clothings. 2. Never taste a chemical or inhale extensively its vapours until you are asked to do so by your teacher. 3. When a chemical is not in use, its container should be closed tightly to prevent it from spilling or its vapours diffusing in air to cause irritation. 4. If a chemical reagent gets into your eyes or mouth or on the skin, wash the affected areas immediately with cold water and report the incident to your teacher or laboratory incharge. 5. In order to neutralise acid spills on the clothing or skin, use a very dilute ammonia or sodium bicarbonate solution. 6. Keep inflammable chemicals like alcohol acetone etc., away from the burner. 7. Never add water to a concentrated acid like sulphuric acid. Such an addition generates a lot of heat which may break the glass container causing a dangerous spill. Always add acid to water slowly, stirring continuously. 8. Never throw a burning matchstick or a burning paper into a sink where it may ignite a discarded flammable liquid. 9. You are required to take extra precautions while heating a chemical or mixture in a glass container. Some of these precautions are briefly described below : (a) To heat a chemical substance in a test tube, apply the flame at the upper layer of the liquid as shown in the figure. Never apply the flame at the bottom of the test tube as it may cause the liquid to boil over. Moreover, the test tube should first be heated gently and then strongly at the outer part of the flame, with continuous shaking. (b) While heating the contents of a test tube be sure to point the open end of the tube away from your classmates and yourself as shown in the figure. 10. Chemicals can be absorbed through the skin. Thus, it is a good habit to wash your hands immediately after they come in contact with any chemical.

Chemistry is an experimental science and involves various types of observations and transformations in substances. It also involves various principles in the making of such substances. Chemistry helps us to understand nature and various life processes. From the beginning of history, people have been fascinated by the world around them. The distinguishing characteristic of humans is the passion to understand their world. That passion has created science. The word science is derived from Latin word scientia which means ‘knowledge’. Thus, science is the term for the broad field of human knowledge concerned with facts that are explained logically by rules, patterns or principles. Areas of Science :Science is divided into separate areas of study, such as astronomy, biology, geology, chemistry, physics and mathematics. Although more recently attempts have been made to combine traditionally separate disciplines under such headings as life sciences and earth sciences. These areas are usually jointly referred to as the natural sciences. The physical sciences comprise mathematics, physics and chemistry. The application of science for practical purposes is called technology.

Early history of Chemistry : Many years before chemistry became a science, people knew how to combine certain substances in order to make things. For example, by 2000 B.C., people of Egypt made bronze by melting tin and copper together. They also made glass, jewellery, perfume and wine. All of these objects involved the production and control of chemical changes. However, the people did not know why these changes took place.