二氧化硫的雙語教學(xué)(省常中-房壽高).ppt

1、Sulfur dioxide,江蘇省常州高級中學(xué) 房壽高,一、Preparation of sulfur dioxide,二、Physical properties of SO2,Under normal circumstances ，sulfur dioxide is a kind of colorless gas with a very pungent (pndnt刺激性 )odour . Its density is more than air.,From the preparation, what physical properties can you get?,Easily solu

2、ble in water(1:40). Easily liquefied ,poisonous gas under pressure.,Is it soluble in water?,三、chemical properties of SO2,lets guess,1. Like CO2, SO2 is an acidic oxide,二氧化硅與二氧化碳的比較,CO2 2NaOH Na2CO3+H2O,SO2 2NaOH Na2SO3+H2O,CO2 Na2CO3+H2O 2NaHCO3,Some other important chemical equations.,Like CO2,If y

3、ou Pass SO2 through limewater Ca(OH)2,the limewater turns cloudy. Continuing passing SO2 will eliminate the cloudy condition .,SO2+H2O+CaSO3 = Ca(HSO3 )2,Calcium bisulfite,Enlarge you view,stalagmite stlmait, stlmait 石筍；石筍狀,stalactite stlktait, stlktait,鐘乳石,Na2SO3+CO2, NaHSO3+CO2,+H2O,2,2,Exercises：

4、,To remove the impurity gas of SO2 in CO2 ,which reagent should we choose( ),A. Saturated Na2SO4（aq) B. Saturated NaHCO3(aq) C. SaturatedNaOH(aq) D. Saturated Na2CO3(aq),B,SO2,S,H2SO4,0,+4,+6,氧化性,加還原劑,還原性,加氧化劑,Prediction：Both as oxidizing agent and reducing agent。,Guess from the valence of sulfur,2、

5、reducibility,SO2 Can react with O2、X2 solution （Cl2、Br2、I2）、 H2O2 、 HNO3 、KMnO4(H+)、Fe3+ etc.,2) SO2+Cl2 + H2O=,(Br2、I2 similarly）,HCl+H2SO4,Question： Put some SO2(g) into BaCl2(aq),is there any white precipitation pri,sipitein(沉淀） ?,Then add some drops of H2O2,what will happen？,3）SO2+H2O2=,H2SO4,NO

6、,Yes. Because in acidic solution,NO3has strong oxidability ，it can oxidizeksidaiz SO2 into SO42-.,Discussion： Put some SO2(g) into Ba(NO3)2(aq),is there any white precipitation ?,4）SO2 Can make KMnO4(H+) 、 Fe3+ fade （MnO4- into Mn2+).,5SO2+2MnO4-+2H2O=2Mn2+5SO42-+4H+,SO2+2Fe3+2H2O=SO42-+2Fe2+4H+,3、O

7、xidability,Put some SO2(g) into H2S(aq), what phenomenon can you see?,SO2+2H2S=3S+2H2O,（comproportionation歸中反應(yīng)）,experiments,Disproportionation 歧化反應(yīng),4、Bleaching agent,demonstrative experiment,Bleaching principle：,Temporarily combined into colorless 、unstable material, after a period of time ，it will

8、become originally color.,SO2 can make pigment(色素）fade, such as magenta mdent(品紅）、flowers. It Cannot make purple litmus test solution fade，only make it turn red.,And it can make KMnO4(H+) fade, showing its reducibility, not bleachability (漂白性).,Physical reaction,Chemical reaction,The adsorbability d,

9、s:bbilti （吸附性）of active carbon,combination：Temporarily bleaching,SO2,oxidation ： Permanent bleaching,Bleaching effect,Chlorine water、NaClO、Na2O2、O3、concentrated HNO3, etc.,1、acid rain： the PH of rain water is less than 5.6,三、SO2 and sustainable development,2、The formation process of acid rain,Way ：,

10、2）SO3+H2O=H2SO4,Such as metal oxide In air smoke,Way ：,1） SO2+H2O H2SO3,2）2H2SO3+O2=2H2SO4,3. The sources of SO2（P89) Fossil fuel burning ;sulfur metal mineral smelting(冶煉） ; the industrial production of sulfuric acid, etc.,4) The influence to buildings,2) The damages to the soil 3）The influence to

11、crops and trees,4、The dangers of acid rain and prevention,1) The influence to aquatic organisms(水生生物）,5. Prevention Measures ：,1）Eliminate ilimineit source, develop new energy.（Fundamental measures根本措施）,2）Desulphurization On fossil fuels,3）To deal with the waste gas,Ammonia water：,SO2+2NH3H2O=（NH4）2SO3+H2O,（NH4）2SO3+SO2+H2O = 2NH4HSO3,Exercises,1、Which of the following means to distinguish SO2 and CO2 （ ） A、purple litmus test solution B、smell C、Clear limewater D、magenta (品紅）,BD,2、How to prove that the mixed colorless gases contain SO2 and CO2？,先證明SO2（通過品紅溶液，