Chemical Reaction in Physical Science.pptx

about chemical reaction

1. What is Chemical Reaction and Its Evidences

2. Chemical reaction is another name for chemical change. They break down your food, producing the energy you need to live. Chemical reactions in the engines of cars and buses provide the energy to power the vehicles. Moreover, chemical reactions produce new products. There are things which help us that a reaction is taking place or the evidence of a chemical reaction. What is a Chemical reaction?

3. These are the following: 1. Production of light 2. Evolution of gas 3. Temperature changes 4. Change in intrinsic properties (color, odor) 5. Formation of precipitate

4. Chemical equation is use to represent chemical reaction. It shows a reactant, the starting point and the product, which are the substances formed after the reaction. Symbols are used to represent meanings on the chemical reaction.

5. Magnesium combines with oxygen gas (O 2 ) to produce magnesium oxide. This can also be expressed in skeleton equation 2 Mg (s) + O 2 → MgO The reactants are magnesium (Mg) and Oxygen (O) gas, the product is magnesium oxide (MgO) The reaction of copper sulfate and iron nail is shown below Fe + CuSO 4 → Cu + FeSO 4 The reactants are iron (Fe) and copper sulfate (CuSO 4) , the products are copper (Cu) and Iron II Sulfate (FeSO 4 )

6. Balancing Chemical Equation A balanced chemical equation occurs when the number of the different atoms of elements in the reactants side is equal to that of the products side. Balancing chemical equations is a process of trial and error.

7. S 8 + O 2 SO 2 Mg + O 2 MgO C 6 H 6 + O 2 CO 2 + H 2 O H 2 + Cl 2 HCl

8. Types of Chemical Reaction Chemists classify chemical reactions in order to organize the many reactions that occur daily. Knowing the categories of chemical reactions can help you remember and understand them. It can also help you recognize patterns and predict the products of many chemical reactions. One - way chemists classify reactions is to distinguish among the four types: synthesis, combustion, decomposition, and replacement reactions.

9. Synthesis reaction — a chemical reaction in which two or more substances (A and B) react to produce a single product (AB). A + B → AB 2Na (s) Cl2 (g) → 2NaCI (s) Synthesis reaction

10. Decomposition reaction is one in which a single compound breaks down into two or more elements or new compounds. AB → A + B 2Na N 3(s) → 2Na (s) + 3 N 2 (g) Decomposition reaction

11. Single-replacement reaction - reaction in which the atoms of one element replace the atoms of another element in a compound. A + BX → AX + B Cu (s) + 2AgNO 3( aq ) → 2Ag (s) + Cu (NO 3 ) 2 ( aq ) Single-replacement reaction

12. Double-replacement reactions. The final type of replacement reaction, which involves an exchange of ions between two compounds. AX + BY → AY + BX Ca (OH) 2 ( aq ) + 2HCl( aq ) → CaCl 2 ( aq ) + 2H 2 O(l) Double-replacement reactions.