电极制备及电池电动势的测定

班级：学号：姓名：同组实验者：实验时间：报告成绩：原电池:电池反应：b1=0.01mol.dm-3r-=0.387z=2b2=0.01mol.dm-3r+=0.4T=291.15K正极E+=0.2707负极E-=-0.8327理论计算值：E=1.1034实验测定值：E'=1.079864相对误差Er=2.13%原电池:电池反应：b1=0.01mol.dm-3r-=0.387z=2T=291.15K正极E+=0.2483负极E-=-0.8327理论计算值：E=1.0810实验测定值：E'=1.064675相对误差Er=1.51%原电池:电池反应：b2=0.01mol.dm-3r+=0.4z=2T=291.15K正极E+=0.2707负极E-=0.2483理论计算值：E=0.0224实验测定值：E'=0.017397(查表4-3不同温度甘汞电极电位)E+-E-=Hg(s)+Cu2++2Cl-(饱和)→Hg2Cl2(s)+2Cu(s)E+⊙-(RT/zF)ln(1/aCu2+)=E-⊙-(RT/zF)ln(1/aZn2+)=实验四电极的制备及其电动势的测定Zn(s)|ZnSO4(a1)|CuSO4(a2)|Cu(s)Zn(s)+CuSO4(b2)→ZnSO4(b1)+2Cu(s)E+⊙-(RT/zF)ln(1/aCu2+)=E-⊙-(RT/zF)ln(1/aZn2+)=（白色区域为输入数据区域，其它地方均为自动生成数据）Zn(s)|ZnSO4(a1)|KCl(饱和)|Hg2Cl2,Hg(查表4-3不同温度甘汞电极电位)Zn(s)+Hg2Cl2(s)→Zn2-(b1)+2Hg(s)+2Cl-E+-E-=E+-E-=Hg2Cl2,Hg|KCl(饱和)|CuSO4(a2)|Cu(s)相对误差Er=22.47%思考题：2.测电动势为何要用盐桥？教师评语：1.为什么不能用伏特计测量电池的电动势？答：答：原电池:电池反应：b1=0.1mol.dm-3r-=0.15z=2b2=0.1mol.dm-3r+=0.16T=291.15K正极E+=0.2881负极E-=-0.8157理论计算值：E=1.1038实验测定值：E'=1.82445相对误差Er=65.29%原电池:电池反应：b1=0.1mol.dm-3r-=0.15z=2T=291.15K正极E+=0.2438负极E-=-0.8157理论计算值：E=1.0595实验测定值：E'=1.51867相对误差Er=43.34%原电池:电池反应：b2=0.1mol.dm-3r+=0.16z=2T=291.15K正极E+=0.2881负极E-=0.2438理论计算值：E=0.0443实验测定值：E'=0.05148Zn(s)|ZnSO4(a1)|KCl(饱和)|Hg2Cl2,HgZn(s)+Hg2Cl2(s)→Zn2-(b1)+2Hg(s)+2Cl-(查表4-3不同温度甘汞电极电位)E-⊙-(RT/zF)ln(1/aZn2+)=(查表4-3不同温度甘汞电极电位)E+-E-=E+-E-=Hg2Cl2,Hg|KCl(饱和)|CuSO4(a2)|Cu(s)Hg(s)+Cu2++2Cl-(饱和)→Hg2Cl2(s)+2Cu(s)E+⊙-(RT/zF)ln(1/aCu2+)=Zn(s)|ZnSO4(a1)|CuSO4(a2)|Cu(s)Zn(s)+CuSO4(b2)→ZnSO4(b1)+2Cu(s)E+⊙-(RT/zF)ln(1/aCu2+)=E-⊙-(RT/zF)ln(1/aZn2+)=E+-E-=相对误差Er=16.13%