Introduction of Chemistry

Chemistry has the task of investigating the materials of which the universe is made. It is not concerned with the forms into which they may be fashioned. For example the composition and structure of rubber is of really significance as compared to the shapes into which this has been fashioned like pipes, tyres and sheets etc. The materials are constantly undergoing chance in nature. For example, iron rusts, spirit evaporates, quickly, coal burns, animals digest their food,plants synthesize their own food materials and so on. Chemistry investigates such changes - The conditions under which they occur, the new substances that are formed as their result, and the energy that is absorbed or liverated by them. Chemistry also studies the way in which similar changes can be brought about in the laboratory and on a large scale in industries. As a result of investigation along these lines, chemistry has found how metals can be extracted from their oresm how infertile fields can be made fertile, and how the materials that are found in nature can be converted into thousands of new substances to help feed the race, to cure the sick and to provide such comfort to the common man.

What is Chemisty?

Chemistry is the brand of science which deals with the composition, structure and the properties of matter. It also deals with the changes in matter and principles which govern these chances.
Chemistry is the study of matter and energy and the interactions between them.
Chemistry tends to focus on the properties of substance and the interactions between different types of matter, particularly reactions that involve electrons.
Physics tends to focus more on the nuclear part of the atom, as well as subatomic realm (kingdom). Really, they are two sides of same coin.

Properties 

The characters of substances (matters) by which they are identified and distinguished from one another are called properties.

1. Physical Properties 

Properties that do not involve chemical changes are called physical properties. Physicial properties refer to the nature of matter such as physical state, mass of a given volume, color, heat conductivity, electrical conductivity, melting point and boiling point.

2. Chemical Properties 

The properties of substance that involve chemical changes are called chemical properties.
For Example : Rusting of icon, burning of sui gas etc.

Changes

Matter undergoes certain as a certain changes as a result of the application of energy. Thera are two types of chancges physical change and chemical change.

1. Physical Change

A physical change is a change that takes place in the physical properties of a material but not in its composition or a chemical identity.
For example Ice (solid state) melts into water (liquid state) and it evaporates into steam (gaseous state).
Chemical composition of water remains same but only its physical state changes.

2. Chemical Change 

A chemical change of chemical reaction is the change that takes place in chemical properties of a substance. During chemical change a substance is changed into new one that has a different chemical composition.
Chemical change or reaction is the rearrangement of the atoms of molecules.
Electrolysis of water, rusting of iron etc are examples of a chemical change.

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