Question

An Isosbestic point is a:

• A. Specific wavelength at which a single component has maximum absorptivity
• B. Specific wavelength at which the solvent has maximum absorptivity
• C. Specific wavelength at which two or more components have the same absorptivity
• D. Specific wavelength at which extinction coefficient of a component is zero

Answer 1

The Correct Option is C

Step 1: Understanding the concept of the isosbestic point. - An isosbestic point occurs when the absorbance of a mixture remains constant despite changes in concentration of two or more components. - This indicates that at a specific wavelength, the total absorptivity remains unchanged. 

Step 2: Explanation of incorrect options. 
- (A) Specific wavelength at which a single component has maximum absorptivity: Incorrect, because an isosbestic point involves two or more components, not a single component. 
- (B) Specific wavelength at which the solvent has maximum absorptivity: Incorrect, as the isosbestic point is related to solute absorbance, not solvent. 
- (D) Specific wavelength at which extinction coefficient of a component is zero: Incorrect, because extinction coefficients are nonzero at isosbestic points. 

Step 3: Selecting the correct option. Since an isosbestic point is defined as a wavelength where two or more components have identical absorptivity, the correct answer is (C) Specific wavelength at which two or more components have the same absorptivity.