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Principles of Instrumental Analysis, 6th ed. Chapter 9
 
 3
9-6. The alcohol reduces the surface tension of the solution leading to smaller droplets. It 
may also add its heat of combustion to the flame leading to a slightly higher temperature 
compared to water which cools the flame. Alcohol also changes the viscosity of the 
solution which may increase the nebulizer uptake rate. All of these factors can lead to a 
great number of Ni atoms in the viewing region of the flame. 
9-7. At hih currents, more unexcited atoms are formed in the sputtering process. These atoms 
generally have less kinetic energy than the excited atoms. The Doppler broadening of 
their absorption lines is thus less than the broadening of the emission lines of the faster 
moving excited atoms. Hence, only the center of the line is attenuated by self-absorption. 
9-8. (1) Employ a higher temperature flame (oxyacetylene). (2) Use a solvent that contains 
ethanol or another organic substance. (3) Add a releasing agent, a protective agent, or an 
ionization suppressor. 
9-9. The population of excited atoms from which emission arises is very sensitive to the flame 
temperature and other conditions. The population of ground state atoms, from which 
absorption and fluorescence originate, is not as sensitive to these conditions since it is a 
much larger fraction of the total population. 
9-10. Nebulization: Aqueous solution containg MgCl2 is converted to an aqueous aerosol. 
 Desolvation. The solvent is evaporated leaving solid particles. 
 Volatilization. The remaining water is evaporated and the particles are vaporized. 
 Atomization. Mg atoms are produced 
 Excitation of Mg to Mg* 
 Ionization of Mg to Mg+ 
 Reaction of Mg to form MgOH and MgO