Factor affecting reaction_rate
-
Upload
yingyin1985 -
Category
Technology
-
view
610 -
download
2
Transcript of Factor affecting reaction_rate
![Page 1: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/1.jpg)
Factors affecting Reaction Rate影響反應速率的因素
29-3-2011
![Page 2: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/2.jpg)
Some chefs prevent the browning by brushing the surface of the fruit with lemon juice.
有些廚師為防蘋果褐變,在蘋果表面上塗上檸檬汁。
![Page 3: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/3.jpg)
Why they have different rate of reaction?
為什麼它們有不同的反應速率?
![Page 4: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/4.jpg)
-Brainstorming Time-
How does a reaction successfully happen?
一個化學反應怎樣成功發生?
![Page 5: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/5.jpg)
Collision Theory碰撞理論
For a chemical reaction to occur, the reactant particles must collide with each other. It is so-called effective collision.
一個化學反應需要發生,反應物粒子必須互相碰撞。這被稱之為有效碰撞。
![Page 6: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/6.jpg)
1. Right Orientation
方位正確3. High kinetic energy enough
足夠高的動能
Collision Theory碰撞理論
![Page 7: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/7.jpg)
反應物粒子互相靠近
有效碰撞
無效碰撞
没有發生反應
產生生成物
+
A BA B
AA
BB
B
B
A
A
AA
BB
AA B
B
Collision Theory碰撞理論
Therefore only small fraction of particles can produce effective collision.
因此只有少數粒子能產生有效碰撞。
![Page 8: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/8.jpg)
速率 ∝ 有效碰撞的數目 單位時間
rate ∝ number of effective collisions
unit time
![Page 9: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/9.jpg)
Factors affecting rate of reaction影響反應速率的因素
Concentration of reactants
反應物的濃度3. Temperature
溫度 Surface area of solid reactant
固體反應物的表面面積 Presence of catalyst
催化劑的使用
![Page 10: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/10.jpg)
Investigating effect of concentration of reactant on reaction rate探究反應物的濃度對反應速率的影響
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
![Page 11: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/11.jpg)
Try to design an experiment to investigate the effect of concentration
on rate of reaction
嘗試設計一個實驗去探究濃度對反應速率的影響
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
• Conical flask 錐形瓶
• Stopper and delivering tube 膠塞及膠管
• Syringe and plunger 針筒及栓塞
• Stop-watch 計時器
![Page 12: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/12.jpg)
柱塞
計時錶
Mg
thread 線
HCl (in excess 過量 )
H2 針筒
Plastic tube 膠管
Measure the volume of hydrogen gas evolved 量度反應所釋出的氫氣的體積
plunge
syringeStop-watch
![Page 13: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/13.jpg)
• Concentration of acid 酸的濃度 (0.5 M 、 1.0 M 、 1.5 M 和 2.0 M)
Same mass of Mg and same volume of acid相同質量的鎂,和相同體積的酸
Control Experiment 對照實驗
![Page 14: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/14.jpg)
反應時間 (min)
氫氣的體積
(cm3)Vol. of H2
Time of reaction
![Page 15: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/15.jpg)
Explanation
解釋
濃度較低 碰撞機會較低
濃度較高 碰撞機會較高
濃度上升
Conc. increase
Low concentration Lower chance to collide
High concentration Higher chance to collide
![Page 16: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/16.jpg)
Reaction involving gases涉及氣體的反應
壓強較低 ∴ 碰撞機會較低
壓強較高 / 體積下降 ∴ 碰撞機會較高
壓強上升
Pressure increase
Low Pressure Lower chance to collide
High Pressure Higher chance to collide
![Page 17: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/17.jpg)
Investigate the effect of Temperature on the rate of reaction探究溫度對反應速率的影響
S2O32–(aq) + 2H+(aq) → SO2(g) + S(s) + H2O(l)
交叉隨時間變得越來越模糊。
![Page 18: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/18.jpg)
0.08012.565
0.05717.560
0.04025.055
0.02050.045
0.010100.035
0.004250.022
(s−1)
交叉被完全「遮蔽」的時間 (s)
反應混合物的溫度 (°C)
![Page 19: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/19.jpg)
溫度 (°C)
1
交叉被「遮蔽」所需的時間
![Page 20: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/20.jpg)
Explanation
解釋
反應物粒子的移動速率較慢
反應物粒子的移動速率較快
溫度上升
Temperature increase
Reactant particles move at lower speed
Reactant particles move at higher speed
![Page 21: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/21.jpg)
Investigate the effect of surface area of solid reactant on rate of reaction探究固態反應物的表面面積對反應速率的影響
![Page 22: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/22.jpg)
CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)
Investigate the effect of surface area of solid reactant on rate of reaction探究固態反應物的表面面積對反應速率的影響
塊狀石灰石 粉狀石灰石 Powdered limestone
Lumps of limestone
![Page 23: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/23.jpg)
反應時間 ( 分 )
反應結束
反應結束
塊狀
石灰
石 粉
狀石
灰石
減少的質量
(g)
Experimental Result
實驗結果
Decrease in m
ass
Time of reaction
Reaction ends
Reaction ends
Lumps
of lim
estone
Powde
red lim
estone
![Page 24: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/24.jpg)
Initial rate of powdered limestone is higher than that of lumps of limestone.粉狀石灰石的初速比塊狀石灰石的初速高。
The reaction of powdered limestone finishes earlier.粉狀石灰石的反應較早完結。
Experimental Result
實驗結果
![Page 25: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/25.jpg)
Explanation
解釋
總表面積 = (2 × 2) × 6 cm2
= 24 cm2
總表面積 = (1 × 1) × 6 × 8 cm2
= 48 cm2
2 cm 1 cm
![Page 26: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/26.jpg)
固體的表面面積較小 碰撞機會較低
固體的表面面積較大 碰撞機會較高
表面面積增加
Increase in surface area
Smaller surface area of solid
lower chance to collide
larger surface area of solid
higher chance to collide
Explanation
解釋
![Page 27: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/27.jpg)
Check Point Lumps of coal can be barely ignited. However, coal dust
in coal mines is one of the causes of explosive combustion. Explain.
煤塊很難點燃,但煤礦中的煤粉卻是引致爆炸性燃燒的原因之一。試加以解釋
ANS: Coal dust is very finely divided state, with very large surface area in contact with oxygen in air. It can be ignited easily.
煤粉是極小的煤。由於煤粉與空氣中的氧的接觸表面面積極大,因此極之易燃。
![Page 28: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/28.jpg)
Investigate the effect of catalyst on reaction rate探究催化劑對反應速率的影響
• Catalyst is a substance that changes(usually increases) the rate of a reaction without being used up.
• 催化劑是能改變 (通常提升 ) 反應速率但不會被消耗的物質。
![Page 29: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/29.jpg)
2H2O2(aq) → 2H2O(l) + O2(g)
Decomposition of hydrogen peroxide過氧化氫的分解作用
2H2O2(aq) → 2H2O(l) + O2(g)MnO2(s)
vs.
![Page 30: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/30.jpg)
計時錶
棉花塞子
少量固態MnO2
已知體積的標準 H2O2(aq)
電子天平
Cotton wool plug
Measured volume of standard H2O2(aq)Stop-watch
Small amount of solid MnO2
Electronic balance
Experimental setup
實驗設置
![Page 31: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/31.jpg)
加入MnO2
没有加入MnO2
時間 (min)
反應混合物的質量
(g)
Mass of reaction m
ixture
Without MnO2
With MnO2
Time
Experimental Result
實驗結果
![Page 32: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/32.jpg)
The industrial use of catalyst催化劑在化學工業上的應用
Haber process哈柏法
Contact process接觸法
N2(g) + 3H2(g) 2NH3(g)Iron powder鐵
粉 450°C 、 250 atm
2SO2(g) + O2(g) 2SO3(g)V2O5
450°C 、 1 atm
![Page 33: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/33.jpg)
Chemical reaction within living cells are mostly catalysed by enzymes.
生物細胞內的化學反應大多數是被酶催化的
We call enzymes biological catalysts. 我們將酶稱為生物催化劑
Catalysts in biological systems生物體系上的催化劑
![Page 34: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/34.jpg)
![Page 35: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/35.jpg)
![Page 36: Factor affecting reaction_rate](https://reader034.fdocuments.net/reader034/viewer/2022052622/55978cf21a28ab641e8b4647/html5/thumbnails/36.jpg)
Catalysts in biological systems生物體系上的催化劑
Enzyme involved in the browning of fruits
導致水果褐變的酶
Enzyme in humans 人體內的酶人體內的酶
Enzyme in yeast
酵母內的酶酵母內的酶