The Tollen’s test for the presence of reducing sugars (say, in a urine sample) i

Question

The Tollen’s test for the presence of reducing sugars (say, in a urine sample) involves treating the sample with silver ions in aqueous ammonia. The result is the formation of a silver mirror within the reaction vessel if a reducing sugar is present. Using glucose to illustrate this test, the redox reaction occurring is

C6H12O6 (aq) + 2 Ag+1 (aq) + 2OH -1 (aq) à C6H12O7 (aq) + 2 Ag(s) + H2O (l)

What has been oxidized?

What has been reduced?

What is the oxidizing agent?

What is the reducing agent?

Show/ explain how you derived your answer.

Explanation / Answer

Glucose is converting into gluconic acid. Glucose is here oxidized. (addition of oxygen is is called oxidation).

Silver is reduced here (decrease in oxidation number from +1 to 0)

Here silver is oxidizing agent (it is going reduction and oxidizing glucose)

Here glucose is reducing agent (glucose is going oxidation and redcuing silver)

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.