1. Chemical Reactions in a Car Engine a) complete combustion: 2 C 8 H 18 (l) + 25 O 2 (g)  16 CO 2 (g) + 18 H 2 O (g) gasoline A tiny fraction of the gasoline doesn’t burn & is released through the car’s exhaust to the atmosphere.

2. Environmental Issues CO 2 & H 2 O are both greenhouse gases (GHG). infrared (IR) radiation

3. b) formation of nitrogen oxides: 2 NO (g) + O 2 (g)  2 NO 2 (g) N 2 (g) + O 2 (g)  2 NO (g)

4. Environmental Issues 1.Nitrogen oxides are a component of smog. 2. Nitrogen oxides react with sunlight & unburned gasoline to form ground level ozone.

5. Ground level ozone causes: cracked tires & windshield wipers respiratory distress

6. 3. Nitrogen oxides also contribute to the formation of acid rain.

7. Treating Car Exhaust catalytic converter

8. A catalytic converter will:  decompose nitrogen oxides:  change the unburned gasoline into carbon dioxide & water 2 NO 2 (g)  N 2 (g) + 2 O 2 (g)

9. How Do Catalytic Converters Work? Catalytic converters contain precious metals such as platinum, palladium, & rhodium that act as catalysts. A catalyst is a substance that makes a reaction happen faster without being used up in the reaction.