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1、各種緩沖液的配制方法Na2HPO4-檸檬酸鈉緩沖液PH0.2mol/LNa2HPO4(ml)0.1mol/L檸檬酸鈉(ml)PH0.2mol/LNa2HPO4(ml)0.1mol/L檸檬酸鈉(ml)2.20.419.65.210.729.282.41.2418.765.411.158.852.62.1817.825.611.608.402.83.1716.835.812.097.913.04.1115.896.012.637.373.24.9415.066.213.226.783.45.7014.306.413.856.153
2、.66.4413.566.614.555.453.87.1012.906.815.454.554.07.7112.297.016.473.534.28.2811.727.217.392.614.48.8211.187.418.171.834.69.3510.657.618.731.274.89.8610.147.819.150.855.010.309.708.019.450.55Na2HPO4。2H2O,分子量=178.050.2mol/L溶液含35.61g/L檸檬酸.H2O,分子量=210.140.1mol/L溶液含21.0
3、1g/L檸檬酸-檸檬酸鈉緩沖溶液(0.1mol/L)PH0.1mol/L檸檬酸(ml)0.1mol/L檸檬酸鈉(ml)PH0.1mol/L檸檬酸(ml)0.1mol/L檸檬酸鈉(ml)3.018.61.45.08.211.83.217.22.85.27.312.73.416.04.05.46.413.63.614.95.15.65.514.53.814.06.05.84.715.34.013.16.96.03.816.24.212.37.76.22.817.24.411.48.66.42.018.04.610.39.76.61
4、.418.64.89.210.8檸檬酸.H2O,分子量=210.140.1mol/L溶液含21.01g/L檸檬酸鈉.2H2O,分子量=294.12;0.1mol/L溶液含29.4g/L資料醋酸緩沖液(0.2mol/L,18℃)PH0.2mol/LNaAC(ml)0.2mol/LHAC(ml)PH0.2mol/LNaAC(ml)0.2mol/LHAC(ml)3.60.759.254.85.904.103.81.208.805.07.003.004.01.808.205.27.902.104.22.657.355.48.601.4
5、04.43.706.305.69.100.904.64.905.105.89.400.60NaAC.3H2O,分子量=136.090.2mol/L溶液含27.22g/L(1)醋酸鹽溶液的配制:醋酸-醋酸鈉緩沖液(pH3.6)???取醋酸鈉5.1g,加冰醋酸20ml,再加水稀釋至250ml,即得。????????醋酸-醋酸鈉緩沖液(pH3.7)??取無(wú)水醋酸鈉20g,加水300ml溶解后,加溴酚藍(lán)指示液1ml及冰醋酸60~80ml,至溶液從藍(lán)色轉(zhuǎn)變?yōu)榧兙G色,再加水稀釋至1000ml,即得。醋酸-醋酸鈉緩沖液(pH3.8)??取2
6、mol/L醋酸鈉溶液13ml與2mol/L醋酸溶液87ml,加每1ml含銅1mg的硫酸銅溶液0.5ml,再加水稀釋至1000ml,即得。醋酸-醋酸鈉緩沖液(pH4.5)????取醋酸鈉18g,加冰醋酸9.8ml,再加水稀釋至1000ml,即得。????醋酸-醋酸鈉緩沖液(pH4.6)????取醋酸鈉5.4g,加水50ml使溶解,用冰醋酸調(diào)節(jié)pH值至4.6,再加水稀釋至100ml,即得。????醋酸-醋酸鈉緩沖液(pH6.0)????取醋酸鈉54.6g,加1mol/L醋酸溶液20ml溶解后,加水稀釋至500ml,即得。用醋酸和醋
7、酸鈉配制的緩沖溶液的PH=PKa+lg[C(NaAc)/C(HAc)](在此,C(HAc)指醋酸的濃度,C(NaAc)指醋酸鈉的濃度,Ka是醋酸的解離常數(shù)=1.8*10-5(1.8乘10的-5次方),PKa=-lgKa=4.75,將PH=5.5代入,可得C(NaAc)/C(HAc)=5.6通常我們配制時(shí)會(huì)使C(HAc)=0.1mol/L,或是C(HAc)=0.2mol/L等。若是配制C(HAc)=0.1mol/L,則C(NaAc)=0.56mol/L稱(chēng)量醋酸鈉固體質(zhì)量為82*0.56=46克量取冰醋酸體積為0.1*1000/1
8、7.5=5.7mL。將稱(chēng)好的醋酸鈉和量好的冰醋酸加入1000mL水中溶解、攪拌均勻即可。當(dāng)然若想配制其它的濃度,也可照公式計(jì)算即可,通常緩沖溶液不能配的太稀,否則緩沖能力要下降,太濃的話又浪費(fèi)試劑。苯二甲酸氫鉀-氫氧化鈉緩沖液PH0.1mol/LNaOH(ml)0.2mol/