1. Chemical reactions and equations.pptx

Chemical reactions and equations is 10th class topic chapter-1 from ncert syllabus and covers basics on chemical reactions and equations

1. Task1

1. The change in physical properties like shape and size of a substance is called ----------- 2. A new substance is formed in ---------- change.

3. When magnesium ribbon is burnt the white powder obtained is -----------. .

2. 4. The insoluble substance formed in a chemical reaction is called -----------. 5. ---------- gas is released when dilute Hcl is added to zinc granules.

3. Task1 1. The change in physical properties like shape and size of a substance is called physical change 2. A new substance is formed in chemical change.

3. When magnesium ribbon is burnt the white powder obtained is Magnesium Oxide.

4. 4. The insoluble substance formed in a chemical reaction is called Precipitate 5. H 2 gas is released when dilute Hcl is added to zinc granules.

5. WORKSHEET 1.why should a magnesium ribbon be cleaned before burning in air ? 2.How can we identify a chemical change? 3. write the difference between physical change and chemical change? 4. what are the observations made when dilute Hcl is added to zinc granules.

6. Task 2
1. The substance that undergo a chemical change are called-------------. 2.In a chemical equation an arrow represents -------------------.

3.Products are written on --------side of the arrow.

7. 4.A chemical reaction in which no. of atoms of each element is same before and after reaction is called ----------------.

5.Mass can neither be created nor ---------------.

6. An unbalanced equation is called -------------.

8. Task 2 1. The substance that undergo a chemical change are called reactants 2.In a chemical equation an arrow represents direction of reaction 3.Products are written on RHS of the arrow.

9. 4.A chemical reaction in which no. of atoms of each element is same before and after reaction is called balanced equation 5.Mass can neither be created nor destroyed 6. An unbalanced equation is called skeletal equation

10. Task3

1.A reaction in which single product is formed from two or more rectants is called ------------- reactions.

2.A reaction in which heat is evolved is called------------- reaction.

11. 3.In decomposition reactions, -------------breaks down to give simpler products.

4.--------------is an example for decomposition reaction where current is used as energy. 5. when white silver chloride is placed in sunlight it turns into--------color.

12. Task-3 1.A reaction in which single product is formed from two or more rectants is called combination reactions. 2. A reaction in which heat is evolved is called exothermic reaction. 3.In decomposition reactions, reactant breaks down to give simpler products.

13. 4. Electrolysis of water is an example for decomposition reaction where current is used as energy. 5.when white silver chloride is placed in sunlight it turns into yellow color .

14. Task-4 1.A chemical reaction in which one element replace another element from its compound is called --------------- 2.zn+cuso4= ---------- + ----------. 3.A -------------- reactive metal can replace a ---------- reactive metal from its compound.

15. 4. A chemical reaction in which precipitate is formed is caled ---------- reaction. 5.Na2so4+2 Bacl ---- ------ + -------.

16. Task-4 1.A chemical reaction in which one element replace another element from its compound is called displacement reaction 2. Zn+CuSo4  ZnSo4 + Cu 3.A more reactive metal can replace a less reactive metal from its compound.

17. 4. A chemical reaction in which precipitate is formed is called precipitation reaction. 5.Na2So4+2 Bacl  2Nacl + 2Baso4

18. Task-5 1.Addition of oxygen is called _________ reaction. 2.In ZnO + C  Zn + CO , ______ is reduced. 3. A reaction in which both oxidation and reduction8 takes place is called _______ reactions.

19. 4. Black coating on silver is an example of __________ . 5. The taste or smell of food materials change after some time due to _____________ process.

20. Task-5 1.Addition of oxygen is called oxidation reaction. 2.In ZnO + C  Zn + CO, Z n is reduced. 3. A reaction in which both oxidation and reduction8 takes place is called redox reactions.

21. 4. Black coating on silver is an example of corrosion 5. The taste or smell of food materials change after some time due to rancidity process