It is common in mass spectrometry to assume that the mass of a cation is the same as that of its parent atom. (a) Using data in Table, determine the number of significant figures that must be reported 1? 1? +? before the difference in masses of ? H and ? H? is significant. Table Comparison of the Proton, Neutron, and Electron 1? (b) What percentage of the mass of an ? H atom does the electron represent?
Solution : Step 1 : (a) Finding the number of significant figures that have to be reported from table given : Significant figures refers to the number of single digits (0 through 9 inclusive) in the coefficient of an expression in scientific notation . Here significant figures are the number of single digits in the mass that is given in the table. The number of significant figures that must be reported according to table given will be 5 significant figures.