0
Upcoming SlideShare
×

# Rates of reaction

9,553

Published on

Published in: Education
3 Likes
Statistics
Notes
• Full Name
Comment goes here.

Are you sure you want to Yes No
• Be the first to comment

Views
Total Views
9,553
On Slideshare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
135
0
Likes
3
Embeds 0
No embeds

No notes for slide

### Transcript of "Rates of reaction"

1. 1. Rates Of Reaction<br />Flow Of Learning<br />
2. 2. Meaning Of Rate Of Reaction<br />MEASUREMENT OF RATES OF REACTION:<br /><ul><li>Plot graph of quantity of product / </li></ul>reactant against time<br /><ul><li>Calculate the average rate of reaction
3. 3. Calculate the rate of reaction at the specific time from the graph.</li></ul>EXPLANATION FOR THE RATE OF REACTION BASED ON COLLISION THEORY:<br /><ul><li>Particle Size
4. 4. Concentration
5. 5. Temperature
6. 6. Catalyst </li></ul>-The meaning of Collision Theory.<br />-To explain how each factor increases <br />
7. 7. <ul><li>Experiment On Effect Of Surface Area
8. 8. Experiment On Effect Of Concentration
9. 9. Experiment On Effect Of Temperature
10. 10. Experiment On Effect Of Catalyst</li></ul>Is proven by<br />
11. 11. How KFC can cook Fried chicken in quickly?<br />
12. 12. Application of The Rate Of reaction In daily Activities<br />
13. 13. Observable changes in quantity that use to determine rate of reaction<br />Meaning rate of reaction<br />Unit for rate of reaction<br />Avarage rate of reaction<br />Measurement <br />Rate Of Reaction<br />Rate Of reaction at specific time<br />Factors that affect rate of reaction<br />Rate Of Reaction<br />
14. 14. Rate <br />Speed = total Distance/Total time<br />K.L<br />J.B<br />
15. 15. Speed=<br />Speed=<br />=<br />=<br />= 100km/h<br />= 300km/h<br />
16. 16. Reaction Types<br />2<br />1<br />Chemical<br />Bonds are made / broken<br /> Change in oxidation states<br /> Plasma<br />Li<br />+1<br />P+1<br />P+1<br />
17. 17. Chemical properties/ changes/ reactions (i.e., reactivity, combustibility).<br /> development of a gas, formation of precipitate, and change in color).<br />Reactivity<br />Combustibility<br />Gas formation <br />Precipitate<br />Color change<br />
18. 18. Hydrogen-VERY reactive.<br />Helium-Non-reactive.<br />
19. 19. The speeds of reactions are very varied<br /><ul><li>Rusting is a ‘slow’ reaction, you hardly see any change looking at it!
20. 20. The weathering of rocks is an extremely very slow reaction. </li></ul>weathering of rocks <br />
21. 21. The fermentation of sugar to alcohol is quite slow but you can see the carbon dioxide bubbles forming in the 'froth' in a laboratory experiment or beer making in industry! <br />Bubble gas<br />
22. 22. <ul><li>A faster reaction example is magnesium reacting with hydrochloric acid to form magnesium chloride and hydrogenor the even faster reaction between sodium and water to form sodium hydroxide.
23. 23. Combustion reactions e.g. when a fuel burns in air or oxygen, is a very fast reaction.</li></li></ul><li>Combustibility<br />The tendency to react with Oxygen, releasing heat.<br />O2 <br />BURNING<br />
24. 24. evidence of Chemical Change:<br />development of a gas<br /> formation of precipitate<br /> change in color<br />
25. 25. Meaning Of Rate Of Reactions<br />The rate of reaction is a measurement of the change in the quantity of reactant or product against time: <br />Rate Of Reaction= Change in quantity of reactant / product <br />Time taken<br />Student ans: Changes of reactant or product against time (0 Mark)<br />
26. 26. Meaning Of Rate Of Reaction<br />A rate of reaction is high if the reaction occurs fast within a short period of time..<br />A rate of reaction is low if the reaction occurs slowly within a long period of time..<br />A rate of reaction is inversely proportional to time: <br /> Rate of reaction α 1<br /> time taken<br />
27. 27. Meaning Of Rate Of Reactions<br />The Higher rate of reaction the shorter time taken to complete the reaction<br />The lower rate of reaction the longer time taken to complete reaction<br />granule<br />powder<br />5 minute <br />1 minute <br />Which is the higher rate of reaction?<br />
28. 28. CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />
29. 29. CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />
30. 30. Observable changes<br />The change in amount of reactant / product that can be measured :<br /><ul><li>Decrease in total quantity of mass / concentration of the reactant per unit of time.
31. 31. Increase in total amount of mass / concentration of the product of reaction per unit of time
32. 32. Total volume of the gas released.
33. 33. Formation of precipitate.</li></li></ul><li>Decrease in total quantity of mass / concentration of the reactant per unit of time.<br />
34. 34. Increase in total amount of mass / concentration of the product of reaction per unit of time <br />
35. 35. Total volume of the gas released.<br />CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />Deliverytube<br />Conical flask<br />burette<br />water<br />Must shade!<br />
36. 36. Formation of precipitate.<br />Na2SO3+2HCl->NaCl+S+SO2+H20<br />PERCIPITATE<br />stopwatch<br />
37. 37. Precipitatethe formation of insoluble ionic compounds.<br />Does NOT dissolve in water.<br />
38. 38. Example:Study the reaction: Between calcium carbonate and excess 1 mol dm-3 hydrochloride acid.CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />
39. 39. CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />
40. 40. Observable changes<br />CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />stopwatch<br />
41. 41. Observable changes<br />CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />Hydrometer <br />
42. 42. Observable changes<br />CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br />Hydrometer <br />
43. 43. Observable changes<br />CaCO3 (s) + 2HCl (aq) -> CaCl2(aq) + H2O + CO2 (g)<br />Displacement Of water<br />
44. 44. Remember !!!<br />CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + H2O + CO2 (g)<br /><ul><li>Quantities of reactant will decreases against time
45. 45. Quantities of product will increases against time</li></li></ul><li>Measurement Rate Of Reaction <br />Two ways to measure rate of reaction.<br />Average Rate Of Reaction. : <br />It is determined by calculating the total amount of reactant used or the total amount of product formed in a specific time.<br />Rate Of Reaction at a specific time :<br />It is determined by calculating the gradient of the graph at the time.<br />
46. 46. Introduction to the Rate of Reaction<br />A reaction between small pieces of excess calcium carbonate with 80 cm3 hydrochloric acid 0.05M is conducted a laboratory to study the rate of reaction at interval time. The volume of gas released is recorded in the table below.<br />
47. 47. 40<br />40<br />30<br />30<br />27.00cm3<br />37.00cm3<br />Volume : 37-27=10 cm3<br />
48. 48. (a)<br />Draw an apparatus to shows how this experiment <br />can be conducted at laboratory.<br />Must label the diagram!<br />
49. 49. x<br />x<br />
50. 50. √<br />√<br />
51. 51. √<br />√<br />
52. 52. (b)<br />Write a balance chemical equation for this reaction.<br />CaCO3 (s) + 2HCl (aq) -> CaCl2(aq) + H2O + CO2 (g)<br />
53. 53. (c)<br />CaCO3 + 2HCl -> CaCl2 + H2O + CO2<br />CaCO3 + 2H++2Cl- -> Ca2++2Cl- + H2O + CO2<br />CaCO3 + 2H++ -> Ca2++ H2O + CO2<br />Remember !!!<br />Only separate soluble salt <br />Don’t separate covalentand insoluble salt<br />
54. 54. (d)<br />Carbon dioxide gas<br />
55. 55. (e)<br />A reaction between small pieces of excess calcium carbonate with 80 cm3hydrochloric acid 0.05M is conducted a laboratory to study the rate of reaction at interval time.<br />Number of mole in the solution will use :<br />MV<br />Mol, n <br />=<br />1000<br />0.05(80)<br />=<br />1000<br />=<br />0.004 mol<br />
56. 56. (f)<br />CaCO3 + 2HCl -> CaCl2 + H2O + CO2<br />From the chemical equation :<br />Mole Ratios:<br />2 mol HCl : 1 mol CO2<br />0.004 mol HCl<br />:<br />0.004 mol HCl<br />×<br />1 mol CO2<br />2 mol HCl<br />=<br />0.002 mol CO2<br />Volume of gas Co2 at room condition<br />=<br />0.002×24 <br />0.048 dm3<br />=<br />
57. 57. (g)<br />Because some of carbon dioxide gas can escape to surrounding during the experiment.<br />
58. 58. (h)<br />
59. 59. Volume of CO2, cm3<br />Connect the point without using ruler!<br />Not all the point is connected<br />Time , s<br />
60. 60. Volume of CO2 cm3<br />Cannot like this graph<br />Straight line<br />It’s must be smooth graph<br />Time s<br />
61. 61. (i)<br />Average Rate Of reaction<br />The average rate of reaction in the first 90 seconds.<br />= The total volume of gas released in the first 90 seconds<br /> Time taken<br />33.5÷90=0.372 cm3s-1<br />unit<br />= <br />Not cm3 per second<br />
62. 62. i(ii)<br />The average rate of reaction in the whole experiment.<br />= The total volume of gas released in the whole experiment<br /> Time taken<br />47.5÷180= 0.264cm3s-1<br />=<br />
63. 63. (h)<br />Volume of gas against time<br />y<br />x<br />α<br />How to fit your scale in graph?<br />For y: use ratio 5: 10 <br />Check it’s enough by 5÷10=0.5<br />Maximum volume 47.5÷0.5=95 small boxes <br />How about x:?<br />30÷10=3<br />Maximum 240÷3=80small boxes<br />
64. 64. Analysis of Data<br />Rate of reaction at t second = gradient AB<br /> = p/q cm3 s-1<br />Total volume of Hydrogen gas/cm3<br />Tangent is a line that touch just 1 point of graph in order to calculate gradient<br />B<br />Tangent <br />p<br />A<br />q<br />Cannot take directly at x<br />t<br />Time (second)<br />
65. 65. Tangent <br />Cannot touch more than 2 point because each of point have different gradient<br />Only touch 1 point of curve<br />
66. 66. tangent<br />α<br />
67. 67. Analysis of data<br />Total Volume of CO2(cm3)<br />F<br />D<br />E<br />Rate of reaction at t1 = gradient AB<br />B<br />Rate of reaction at t2 = gradient CD<br />C<br />Rate of reaction at t3 = gradient EF<br />Each of point have different gradient!<br />A<br />t1<br />t3<br />t2<br />Time (second)<br />
68. 68. Two method to calculate tangent:<br />Total volume of Hydrogen gas/cm3<br />number of small boxes ×value of <br />1 small unit box<br />B<br />Tangent <br />Y<br />A<br />X<br />Time (second)<br />
69. 69. First Method<br />Gradient of graph:<br />Total volume of Hydrogen gas/cm3<br />m = ΔY<br />ΔX<br />B<br />m = Y2-y1<br />y2<br />X2-x1<br />Tangent <br />A<br />y1<br />Time (second)<br />x1<br />x2<br />
70. 70. Analysis of Data<br />Rate of reaction at t second = gradient AB<br /> = p/q cm3 s-1<br />Total volume of Hydrogen gas/cm3<br />B<br />Tangent <br />p<br />A<br />q<br />t<br />Time (second)<br />
71. 71. Analysis of data<br />Total Volume of CO2(cm3)<br />F<br />D<br />E<br />Rate of reaction at t1 = gradient AB<br />B<br />Rate of reaction at t2 = gradient CD<br />C<br />Rate of reaction at t3 = gradient EF<br />A<br />t1<br />t3<br />t2<br />Time (second)<br />
72. 72. From the answer of question (i) (iii) and (i) (iv), <br />make a conclusion from the <br />calculation of this experiment.<br />(j)<br />Ans : Rate of reaction will decreases<br />
73. 73. (k)<br />Explain why does there is a difference of the rate <br />of reaction at 30 second and 120 second. <br />Ans: Rate of reaction at 30 second is higher because number of particles of reactant is higher than 120 second<br />
74. 74. (l)<br />In your opinion, what will happen to the rate of reaction if, <br /><ul><li>The concentration of acid is increased.
75. 75. A calcium carbonate powder is used in this </li></ul>experiment.<br /><ul><li>The volume of acid is increased.
76. 76. The temperature of acid is increased.
77. 77. A bigger conical flask is used.
78. 78. The conical flask containing acid is shaken. </li>
1. #### A particular slide catching your eye?

Clipping is a handy way to collect important slides you want to go back to later.