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Question 51 pts A breathalyzer is a device used to estimate the blood alcohol content of a suspected drunk driver by measuring the amount of alcohol in one's breath. The fuel cell breathalyzer employs the reaction below: CH3CH2OH(g)+O2(g)→HC2H3O2(g)+H2O(g) When a suspected drunk driver blows his or her breath through the fuel-cell breathalyzer, the device measures the current produced by the reaction and calculates the percent alcohol in the breath. How many moles of electrons are transferred per mole of ethanol, CH3CH2OH, in the reaction?

User Russ Cox
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Answer:

Four moles of electrons

Step-by-step explanation:

The reactions in a breathalyzer are redox reactions. Fuel cell breathalyzers consists of fuel cells with platinum electrodes. The current produced depends on the amount of alcohol in the breath. Detection of alcohol involves the oxidation of ethanol to ethanoic acid. The two half cells set in the process are;

Anode;

C2H5OH(aq) + 4OH^-(aq) ----------> CH3COOOH(aq) + 3H2O(l) + 4e

Cathode;

O2(g) + 2H2O(l) +4e--------> 4OH^-(aq)

Hence four electrons are transferred in the process.

User Cyril Jacquart
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