Question

If a solid or liquid membrane is placed in pure water, the membrane dissolves slightly, producing an equilibrium concentration of the measured ion. This is represented as __________

(a) A constant, Eo

(b) Activity

(c) Blank correction, Cb

(d) Concentration of standard solution, Cs

The question was posed to me in an interview.

Origin of the question is Ion Analyser in section pH Meters and Ion Analysers of Analytical Instrumentation

Answer 1

Correct option is (c) Blank correction, Cb

Explanation: If a solid or liquid membrane is placed in pure water, the membrane dissolves slightly, producing an equilibrium concentration of the measured ion. This is represented as a blank correction, Cb. This is the constant background for all measurements.