Volatility (chemistry) vapor pressure chart (right hand side) displays the vapor pressures dependency for a variety of liquids as a function of temperature. For example, at any given temperature, chloromethane (methyl chloride) has the highest vapor pressure of any of the liquids in the chart. It also has the lowest normal boiling point (−24.2 °C), which is where the vapor pressure curve (the blue line) intersects the horizontal pressure line of one atmosphere (atm) of absolute vapor pressure. Volatility (chemistry) In chemistry and physics, volatility is quantified by the tendency of a substance to vaporize. Volatility is directly related to a substance's
Chemical substance regard. A chemical substance may well be defined as "any material with a definite chemical composition" in an introductory general chemistry textbook. According to this definition a chemical substance can either be a pure chemical element or a pure chemical compound. But, there are exceptions to this definition; a pure substance can also be defined as a form of matter that has both definite composition and distinct properties. The chemical substance index published by CAS also includes several alloys of uncertain composition. Non-stoichiometric compounds are a special case (in inorganic chemistry) that violates the law of constant composition, and for