| 摘要 |
PROBLEM TO BE SOLVED: To provide an ion electrode that does not cause water molecules to permeate internal liquid and has less measurement error associated with a temperature change even if a response film has a property of semi-permeable membrane and a sample of low ion concentration is to be measured.SOLUTION: An ion electrode S1 comprises, in a space partitioned from the outside by a response film S11, an internal liquid S13 and an internal electrode in contact with the internal liquid S13. In the ion electrode S1, a measurable concentration range in which a measuring object ion can be measured is lower than halide ion concentration in the internal liquid of a reference electrode. The internal liquid S13 contains the measuring object ion and the halide ion, and is adjusted so that an osmotic pressure and isothermal intersection point of the internal liquid S13 reach desired values by changing the measuring object ion concentration and the halide ion concentration in the internal liquid S13. The isothermal intersection point is included within the measurable concentration range. |
