JEE Advanced2006ChemistryElectrochemistryActual
Paragraph: Tollen's reagent is used for the detection of aldehyde when a solution of AgNO ₃ is added to glucose with NH ₄ OH then gluconic acid is formed array rr Ag ⁺+e⁻ Ag & E_ red ^ =0.8 ~V C ₆ H ₁₂ O ₆+ H ₂ O Gluconic acid ( C ₆ H ₁₂ O ₇ )+2 H ⁺+2 e⁻ ; & -E_ red ^ =-0.05 ~V Ag ( NH ₃ )₂⁺+e⁻ Ag (s)+2 NH ₃ ; & E_ red ^ =0.337 ~V array [Use 2.303 R T F =0.0592 and F R T =38.92 at 298 ~K ] Question: Ammonia is always
Options
- ANH ₃ combines with Ag ⁺ to form a complex
- BAg ( NH ₃ )₂⁺ is a stronger oxidising reagent than Ag ⁺ .
- CIn absence of NH ₃ silver salt of gluconic acid is formed.
- DNH ₃ has affected the standard reduction potential of glucose/gluconic acid electrode.
Correct answer
D. NH ₃ has affected the standard reduction potential of glucose/gluconic acid electrode.
Step-by-step solution
Ammonia has no effect on the standard reduction potential.