(20 10? Shaanxi simulation) According to the requirements of environmental protection, in cyanide electroplating wastewater treatment, highly toxic CN- is treated with NaClO under the action of cataly

(20 10? Shaanxi simulation) According to the requirements of environmental protection, in cyanide electroplating wastewater treatment, highly toxic CN- is treated with NaClO under the action of catalyst TiO2 particles. (1) According to the meaning of the question, the reaction in A is that NaClO oxidizes CN- ions to CNO-, NaClO has strong oxidation and is reduced to Cl-, and the reaction ionic equation is CN-+CLO-═ CNO-+Cl-; The reaction in B is that CNO- reacts with NaClO under acidic conditions to generate N2, CO2 and Cl2, and the reaction ionic equation is 2cno-+6clo-+8h+N2 =+2co2 =+3cl2 =+4h2o.

So the answer is: 2cno-+6clo-+8h+═ N2 ↑+2co2 ↑+3cl2 ↑+4h2o;

(2) The experimental principle is to determine the quality of carbon dioxide absorbed by the drying tube I, and determine the treatment method of CN-, because N2, CO2, Cl2, H2O, chlorine and water generated by the device B can be absorbed by alkaline lime, which affects the determination of carbon dioxide quality. Therefore, chlorine and water should be removed from the gas entering the drying pipe I, and absorbed by concentrated sulfuric acid, and chlorine should be removed by copper mesh. At the same time, CO2 and water vapor in the air should be prevented from entering the drying tube I to interfere with the experiment. Therefore, the reagent in device C is the purpose of device D to remove Cl2；; The function of drying tube I is to absorb CO2, and the function of drying tube II is to prevent CO2 and water vapor in the air from entering the interference experiment.

So the answer is: concentrated sulfuric acid; Removing Cl2；; Prevent CO2 and water vapor in the air from entering the drying tube I and interfering with the experiment;

(3) The residual CO2 in the device is not completely absorbed, which leads to the low quality of measured CO2 and the measured CN- treatment percentage is lower than the actual value.

So, the answer is: low; The residual CO2 in the device is not completely absorbed;

(4) The weight gain of sodium and calcium in drying tube I is 1.408g, which is the mass of carbon dioxide, and the amount of substance is1.408g/mol = 0.032mol. According to the conservation of carbon, the amount of treated CN- substance is n (CN-) = n (CO2) = 0.032.

So the answer is: 80%