Breathalyzer, fuel-cell

A FIGURE 16.18 Schematic diagram of a fuel-cell breathalyzer... 

The amount of electrical current produced depends on the amount of alcohol in the breath. A higher current reveals a higher blood alcohol level. When calibrated correctly, the fuel-cell breathalyzer can precisely measure the blood alcohol level of a suspected drunk driver. 

A Fuel-cell breathalyzer A suspect blows into the top of this device and blood alcohol level is determined. 

FIGURE 18.19 Fuel-Cell Breathalyzer The fuel-ceU breathalyzer works by oxidizing ethyl alcohol in the breath to acetic acid. The electrical current that is produced is proportional to the concentration of ethyl alcohol in the breath. 

Breathalyzers work because the amount of ethyl alcohol in the breath is proportional to the amount of ethyl alcohol in the bloodstream. One type of breathalyzer employs a fuel cell to measure the amount of alcohol in the breath. The fuel cell... 

Police often use a device called a breathalyzer to measure the amount of ethyl alcohol (C2HgO) in the bloodstream of a person suspected of driving under the influence of alcohol (Figure 18.19 ). Breathalyzers work because the quantity of ethyl alcohol in the breath is proportional to the quantity of ethyl alcohol in the bloodstream. One t5rpe of breathalyzer employs a fuel cell to measure the quantity of alcohol in the breath. When a suspect blows into the breathalyzer, ethyl alcohol is oxidized to acetic acid at the anode ... 

In one type of Breathalyzer (alcohol meter), the quantity of ethanol in a sample is related to the amount of electric current produced by an ethanol-oxygen fuel cell. Use data from Table 19.1 and Appendix D to determine (a) E°en and (b) E° for the reduction of C02(g) to CH3CH20H(g). 

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