Answer:
<em>Properties. The physical properties of organic compounds typically of interest include both quantitative and qualitative features. Quantitative information includes a melting point, boiling point, and index of refraction. Qualitative properties include odor, consistency, solubility, and color.</em>
Fractinal distillation is used in the production of gasoline, distilled water, xylene, alcohol, paraffin, kerosene, and many other liquids.
They discovered that *elements* show increase in atomic numbers across the period.
