Gas-phase ion chemistry Gas-phase ion chemistry Gas phase ion chemistry is a field of science encompassed within both chemistry and physics. It is the science that studies ions and molecules in the gas phase, most often enabled by some form of mass spectrometry. By far the most important applications for this science is in studying the thermodynamics and kinetics of reactions. For example, one application is in studying the thermodynamics of the solvation of ions. Ions with small solvation spheres of 1, 2, 3... solvent molecules can be studied in the gas phase and then extrapolated to bulk solution. Transition state theory is
Mixture of mixture. A "heterogeneous mixture" is a mixture of two or more chemical substances (elements or compounds). Examples are: mixtures of sand and water or sand and iron filings, a conglomerate rock, water and oil, a portion salad, trail mix, and concrete (not cement). A mixture of powdered silver metal and powdered gold metal would represent a heterogeneous mixture of two elements. Making a distinction between "homogeneous" and "heterogeneous" mixtures is a matter of the scale of sampling. On a coarse enough scale, any mixture can be said to be homogeneous, if the entire article is allowed to count as