6. Digestion - proteins are converted into amino acids, carbohydrates into sugars, carbon dioxide, and water, and fats into fatty acids and other products. Breathing - this involves the oxygenation of hemoglobin in the lungs, and the release of carbon dioxide from hemoglobin for expulsion from the body.
Combustion of fuels - driving the car to work involves the combustion of gasoline; heating the home involves the combustion of heating oil, or the burning of coal or wood to produce heat.
Boiling an egg - this causes the denaturation of the protein, albumin, and changes it from a liquid to a solid state.
Dropping an Alka-Seltzer tablet in a glass of water causes a release of carbon dioxide from the bicarbonate of soda and the potassium bicarbonate they contain.
8. The explosions at the TRW plant are damaging because sodium azide (NaN3)is a potent metabolic poison, which acts rapidly and is potentially lethal (CDC, 2003; Los Alamos, 2004). When it mixes with water or comes in contact with solid metals, sodium azide changes rapidly into a toxic gas. The toxic gas has a pungent odor, but may not be sharp enough to give people warning of the danger. An explosion which involves sodium azide may cause burn injuries, as well as exposing people to the toxic gas, hydrozoic acid. The gas is lighter than air, so will rise once formed. It is most dangerous in enclosed spaces where the gas is trapped. The gas prevents the cells of the body from using oxygen, and so th
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