Molecules, Compounds, and Chemical Equations

Almost all aspects of life are engineered at the molecular level, and without understanding molecules we can only have a very sketchy understanding of life itself 

3 Representing Compounds Chemical Formulas and Molecular Models 90 

10 Determining a Chemical Formula from Experimental Data 114 

How MANY DIFFERENT SUBSTANCES EXIST Recall from Chapter 2 that about 91 different elements exist in nature, so there are at least 91 different substances. However, the world would be duU— not to mention lifeless— with only 91 different substances. Fortunately, elements combine with each other to form compounds. Just as combinations of only 26 letters in our English alphabet allow for an almost limitless number of words, each with its own specific meaning, combinations of the 91 naturally occurring elements allow for an almost limitless number of compounds, each with its own specific properties. The great diversity of substances that we find in nature is a direct result of the ability of elements to form compounds. Life, for example, could not exist with just 91 different elements. It takes compounds, in all of their diversity, to make life possible. 

Flammability Explosive Necessary for combustion Used to extinguish flame 

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Chapter 3 Molecules, Compounds, and Chemical Equations A Molecular Compound... 

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