F ACTOR A FFECTING THE R ATE OF C HEMICAL R EACTION Activity 8-9 GROUP 1 Mary Jane TuboImee Jane Calo Glen BenigayMarissa Abacay Myra SolisFred Cañete

I NTRODUCTION A chemical reaction is the process that occurs when two or more substances combine to produce a chemical change. And the rate of chemical reaction can be expressed as the ratio of the change in concentration of reactant (or a product) to change in time. It's useful to be able to predict whether an action will affect the rate at which a chemical reaction proceeds. There are several factors that can influence the rate of a chemical reaction. These include the following: nature of reactivity of the reactants, concentration of the reactants, surface area, temperature, and catalyst.

O BJECTIVE The student will be able to evaluate the several factor affecting the rate of chemical reaction.

A PPARATUS 250-ml beaker Bunser burner 2 dropper 10-ml graduated cylinder (5) 10-ml test tube Tripod Test tube brush 2 test tube holder Test tube rack Thermometer (5) 20-ml test tube Wire gauze

C HEMICALS Liquids: 1.0 M acetic acid (0.5 M, 1.0 M, 1.5 M, 2.0 M) hydrochloric acid 0.3 M manganous sulfate (1.0 M, M) potassium permanganate (1.0 M, 0.25 M) sulfuric acid Solids: Magnesium ribbon

P ROCEDURE A. Nature or Reactivity of the Reaction 1. label 2 test tubes 1 and 2. into test tube 1, place 5.0 ml of 1.0 M of hydrochloric acid soln. then add 1-cm long magnesium ribbon. 2. take note of the time required for complete reaction 3. into test tube 2, place 5.0 ml of 1.0 M acetic acid soln. and then add 1-cm long magnesium ribbon. 4. note also the time required for complete reaction.

B. Concentration of the Reaction 1. fill a 10-ml graduated cylinder with water to the brim. 2. get a piece of paper and crumple it so as to fit the mouth of the cylinder. 3. fill a 250-ml beaker with water. 4. quickly cover the graduated cylinder with the crumpled paper and invert it carefully into the beaker water. 5. be sure that there are no bubbles trapped inside. 6. now, fill the cylinder with 2.0 M hydrochloric acid soln. to the brim. 7. secure a 1-cm long magnesium ribbon and place it in the cylinder.

8. quickly cover the cylinder with the crumpled paper and invert it into the beaker of water. 9. note the time required to collect 5.0 ml of hydrogen gas. 10. repeat the procedure 6 to 9, this time using 1.5 M, and 0.5 M hydrochloric acid soln. and 1-cm long magnesium ribbon.

C.Surface Area of the Reactant 1. place 5.0 ml of 1.0 M hydrochloric acid soln. into each of three clean test tubes. 2. obtain three pieces of 2.0 long magnesium ribbon. 3. to the first test tube, add one piece of magnesium ribbon and note the time required for the reaction to complete. 4. divide the second piece of magnesium ribbon into 8 equal parts and add these into the second test tube. 5. again, take note the time required for the reaction to complete. 6. divide the last piece of magnesium ribbon into very small pieces and add these into the third test tube. 7. note also the time required for the reaction to complete.

D. Catalyst 1. label two test tube 1 and 2. to both test tubes, and 2 ml of 1.0 M oxalic acid and drops of 1.0 M sulfuric acid. 2. to test tube 1, and 1 ml of 0.01 M potassium permanganate and shake the test tube constantly. 3. note the time required for the purple color to disappear. 4.to test tube 2, add 1 ml of M potassium permanganate and quickly add 1 drop of 0.3 M manganous sulfate soln. 5. shake the test tube and note the time required for the purple color to disappear.

E. Temperature 1. place 1.0 ml of M potassium permanganate and 1.o ml of 0.25 M sulfuric acid into each of five 10- ml test tubes. 2. measure 15.0 ml 0.01 M oxalic acid into each of five 20-ml test tubes. 3. place one test tube containing the permanganate and one test tube containing the oxalic acid in a 250- ml beaker of water at room temperature. 4. after five minutes, it can be assumed that the temperature of the reactants is the same as the temperature of the water.

5. rapidly but carefully, pour the potassium permanganate and sulfuric acid soln. into the test tube containing the oxalic acid soln. 6. shake the test tube vigorously, but carefully to allow the reactants to interact. 7. note the time required for the complete decolorization of the permanganate soln.. 8. perform four more trials with temperature 10 *C higher than the previous temperature.

R ESULT AND D ISCUSSION Activity no. 8 Activity no. 9

C ONCLUSION Five important factors control the rate of a chemical reaction. The nature of the reactants, Some elements and compounds, because of the bonds broken or formed, react more rapidly with each other. The surface area exposed, Since most reactions depend on the reactants coming into contact, the surface exposed proportionally affects the rate of the reaction. The concentrations,The reaction rate is usually proportional to the concentrations of the reactants. The temperature, A temperature increase of 10° C above room temperature usually causes the reaction rate to double or triple. The catalyst, Catalysts can either speed up or slow down the rate of a reaction. In general, a factor that increases the number of collisions between particles will increase the reaction rate and a factor that decreases the number of collisions between particles will decrease the chemical reaction rate.

GOD BLESS!!!