1. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions

2. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions A chemical reaction is a chemical change which forms new substances. Chemical Reaction Fermentation of grapes, burning of wood etc. Example :-

3. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Combination reaction Decomposition reaction Displacement reaction Double –displacement reaction Oxidation –reduction reaction Exothermic and endothermic reaction

4. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Combination Reaction The reactions in which two or more substances combine to form a new single substance are called combination reactions. C + O 2 ---> CO 2 E.g.:- Burning of coal

5. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Decomposition Reaction Electrolysis of water gives oxygen gas and hydrogen gas through the decomposition reaction. 2H 2 O ---> 2H 2 + O 2 AB ---> A + B E.g.:- A decomposition reaction is a type of chemical reaction where one reactant yields two or more products. A decomposition reaction is a type of chemical reaction where one reactant yields two or more products.

6. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Displacement Reaction A displacement reaction is a type of reaction where part of one reactant is replaced by another reactant. A + BC ---> AC + B Magnesium displaces hydrogen in water to give magnesium hydroxide and hydrogen gas. Mg + 2H 2 O ---> Mg(OH) 2 + H 2 E.g.:-

7. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Double Displacement Reaction A reaction in which the two reacting ionic compounds exchange their corresponding ions is called a double displacement reaction. A reaction in which the two reacting ionic compounds exchange their corresponding ions is called a double displacement reaction.

8. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Double Displacement Reaction On mixing a solution of silver nitrate with sodium chloride, a white precipitate of silver chloride is immediately formed. E.g.:-

9. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Precipitation Reaction Any reaction that produces an insoluble substance, precipitate, is called a precipitation reaction. E.g.:- On adding a solution of lead nitrate to sodium iodide solution, a yellow precipitate of lead iodide is formed.

10. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Oxidation – Reduction or Redox Reactions Oxidation is the gain of oxygen or loss of hydrogen. Reduction is the loss of oxygen or gain of hydrogen. These reactions involve the gain or loss of oxygen or hydrogen by substances.

11. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Oxidation – Reduction or Redox Reactions E.g.:-

12. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Exothermic Reaction Reactions in which heat is liberated are known as exothermic reactions. E.g.:- Burning of natural gas.

13. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Endothermic Reaction Reactions in which energy is absorbed are known as endothermic reactions. E.g.:- Melting of ice.

14. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions When a metal is attacked by substances around it such as moisture, acids, etc., it is said to corrode and this process is called corrosion. Corrosion

15. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Examples of Corrosion Corrosion Green coating on Copper Black coating on Silver Rusted Iron nails

16. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Methods to Prevent Corrosion Corrosion Painting Painting Greasing Greasing Oiling Oiling

17. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Rancidity It is the chemical decomposition of fats, oils and other lipids that results in undesirable odours and flavours.

18. Element Elements and Compounds Structure of Atom Compounds A compound is a substance composed of two or more elements, chemically combined with one another in a fixed proportion. Water, sugar, salt, carbon dioxide, methane etc are the examples of compounds. Chemical Reactions and Equations Types of Chemical Reactions Rancidity Methods to Reduce Rancidity Adding Antioxidants to Foods containing Oil/Fat Adding Antioxidants to Foods containing Oil/Fat Keeping Foods in Air Tight Containers Keeping Foods in Air Tight Containers