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What is the net redox reaction that occurs when Ag comes into contact with acidic K2Cr2O7?

User Mrdoob
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Answer:

Ag + K2Cr2O7 + H2SO4 → Ag2Cr2O7 + K2SO4 + H2O

Step-by-step explanation:

When silver (Ag) comes into contact with acidic potassium dichromate (K2Cr2O7), the following redox reaction occurs:

Ag + K2Cr2O7 + H2SO4 → Ag2Cr2O7 + K2SO4 + H2O

In this reaction, silver is oxidized from Ag(0) to Ag(I), while potassium dichromate is reduced from Cr(VI) to Cr(III).

The half-reactions for this reaction are as follows:

Oxidation half-reaction:

Ag(0) → Ag+(1) + e-

Reduction half-reaction:

Cr2O7^2-(VI) + 14H+(aq) + 6e- → 2Cr^3+(aq) + 7H2O(l)

To balance the net redox reaction, we need to multiply the oxidation half-reaction by 6 and the reduction half-reaction by 1. This gives us the following balanced net redox reaction:

6Ag(0) + K2Cr2O7(aq) + 14H+(aq) → 6Ag+(aq) + 2Cr^3+(aq) + K2SO4(aq) + 7H2O(l)

Simplified, the net redox reaction is:

Ag + K2Cr2O7 + H2SO4 → Ag2Cr2O7 + K2SO4 + H2O

This reaction is a single displacement reaction, in which silver displaces chromium from potassium dichromate.

User Chiwangc
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