CBSE Class 11 Chemistry Revision Notes Set A

BSE Class 11 Chemistry-Basic Concepts of Chemistry. Revision worksheets, Sample papers, Question banks and easy to learn study notes for all classes and subjects based on CBSE and NCERT guidelines. Students and parents can download free a collection of all study material issued by various best schools in India. The study material has been carefully compiled by the best teachers in India. The students should practice the questions database to get better marks in examination. Please refer to other links for free download of high quality study material. Based on CBSE and NCERT guidelines. Based on the same pattern as released by CBSE every year. Study material for final/ term/ SA1/ SA2 Examinations conducted by various schools affiliated to Central Board of Secondary Education (CBSE) in India and abroad. CBSE Study material has been compiled to help students preparation which will helps the students to concentrate more in areas which carry more marks.

ENJOY CHEMISTRY

1.SOME BASIC CONCEPTS OF CHEMISTRY

Some Important Points and Terms of the Chapter

1.   Anything which has mass and occupies space is called matter.

2.   Matters exist in three physical states viz. solid, liquid and gas. 

3.  In solids, these particles are held very close to each other in an orderly fashion and there is not much freedom of ovement. In liquids, the particles are close to each other but they can move around. However, in gases, the particles are far apart as compared to thosepresent in solid or liquid states and their movement is easy and fast.

4.   Solids have definite volume and definite shape. 

5.   Liquids have definite volume but not the definite shape. They take the shape of thecontainer in which they are placed. 

6.   Gases have neither definite volume nor definite shape. They completely occupy thecontainer in which they are placed. 

7.   A mixture contains two or more substances present in it (in any ratio) which are called its components.

8.   A mixture may be homogeneous or heterogeneous.

9.   In a homogeneous mixture, the components completely mix with each other and its composition is uniform throughout. Sugar solution and air are thus, the examples of homogeneous mixtures. 

10.  In heterogeneous mixtures, the composition is not uniform throughout and sometimes thedifferent components can be observed. For example, the mixtures of salt and sugar, grainsand pulses along with some dirt (often stone) pieces, are heterogeneous mixtures.. 

11.  The components of a mixture can be separated by using physical methods such as simple hand picking, filtration, crystallization, distillation etc.

12.   Pure substances have characteristics different from the mixtures. They have fixedcomposition, Copper, silver, gold, water, glucose are some examples of pure substances. Glucose contains carbon, hydrogen and oxygen in a fixed ratio and thus, like all other pure substances has a fixed composition. Also, the constituents of pure substances cannot be separated by simple physical methods.

13.  An element consists of only one type of particles. These particles may be atoms or molecules. Sodium, copper, silver, hydrogen, oxygen etc. are some examples of elements. They all contain atoms of one type. However, the atoms of different elements are different in nature. Some elements such as sodium or copper, contain single atoms held together as their constituent particles whereas in some others, two or more atoms combine to give molecules of the element. Thus, hydrogen, nitrogen and oxygengasesconsist of molecules in which two atoms combine to give their respective molecules. 

14.  When two or more atoms of different elements combine, the molecule of a compound is obtained. The examples of some compounds are water, ammonia, carbon dioxide, sugar etc. the atoms of different elements are present in a compound in a fixed and definite ratio and this ratio is characteristic of a particular compound.

Please refer to attached file for CBSE Class 11 Chemistry-Basic Concepts of Chemistry