Class 10 chemistry part important notes of chemical reaction

                   

Class 10  chemistry part important  notes  of chemical reaction 

Introduction

·         Chemical changes are undergoing in natures .In chemical changes smallest particles of matters such as atoms or molecules takes part

·         Endothermic reaction require heat whereas exothermic evolution of heat to the surrounding

·         Different between chemical changes and physical changes

 

SN	Physical changes	Chemical changes
1.	Changes of state only	Changes of matters
2.	No new substance are formed	New substance are formed
3.	It is reversible	It is not reversible
4.	New substance formed will posses same properties	New substance formed will posses different properties

 

Endothermic reaction :

Some example

CaCO3    ----------------------   >  CaO  +CO2    (breaking of bond ) heat is required

  Exothermic reaction

C +O2            gives           CO2

Chemical equation

Chemical represent of a chemical reaction is called chemical equation

ESSENTIAL OF CHEMICAL EQUATION

·          it  should represent an actual chemical changes .

·          it should be balanced

·          it should be molecular   

FACTORS OF CHEMICAL EQUACTION

·         heat ,electricity and light energy

·         by contact

·         by dissolving 

·         by pressure

·         by catalyst

Catalyst : A catalyst is a chemical substance that does not takes part in chemical reaction but generally enhances the chemical reaction

 

 

Types of the chemical reaction

1.       combination reaction

2.       decomposition reaction

3.       displacement reaction

4.       acid base reaction

5.       oxidation reaction

6.       isomerism

7.       hydrolysis

8.       polymerization

9.       condensation

COMBINATION  REACTION

 Combine of the two molecules  or more

Examples                 Fe   +   S                      gives                FeS

DECOMPOSITION  REACTION

Breaking of the molecules

CaCO3                       gives           CaO  +CO2   

DISPLACEMENT REACTION

When two or more compound are in state of reaction one element of the compound is displace by another element

Zn +H2SO4                                     ZnSO4 +H2

ACID  BASE REACTION

When acid and base are react with each other and  loss of properties of acid and base both  become neutral is called  acid base reaction .IT is also called as neutralization reaction 

 INFORMATION FOR BALANCED CHEMICAL EQUATION

1.    1.  the names of the reactants and products and theirs molecular formula can be seen

2.     2. the numbers of atoms and molecules that takes places in chemicals reaction .

3.     3. the ratio of the weight of the reaction and products .

4.     4. the types of the chemicals reaction .