Final answer:
The question asks for identification of elements based on mass spectra using a mass spectrometer. Chlorine, sodium, xenon, arsenic-73, and radium are discussed with relevance to their mass-to-charge ratios and positions in the periodic table. Chemical analysis using mass spectrometry is crucial in several fields including environmental science and medicine.
Step-by-step explanation:
The mass spectrum is a tool used by chemists to determine the relative atomic mass of isotopes and to identify elements in a sample. When using a mass spectrometer, a sample is vaporized and ionized; the resulting cations are then separated based on their mass-to-charge ratios in a magnetic field. The peaks on the mass spectrum correspond to these ions and their natural abundances. For example, chlorine has two isotopes, 35 Cl and 37 Cl, with approximate natural abundances reflected by the heights of peaks in its mass spectrum. This process is essential in fields like environmental science, forensics, and medicine.
The provided data on elements and their mass spectra can be used to identify elements in different samples. For instance:
- (a) The alkali metal with 11 protons and a mass number of 23 is sodium (Na).
- (b) The noble gas with 75 neutrons in its nucleus and 54 electrons in the neutral atom is xenon (Xe).
- (c) The isotope with 33 protons and 40 neutrons in its nucleus is arsenic-73 (73As).
- (d) The alkaline earth metal with 88 electrons and 138 neutrons is radium (Ra).
The atomic number and atomic mass of each element are typically found on the periodic table. Elements in the same column share the same number of valence electrons due to similar outer shell configurations, like Li and Na, which both have one valence electron. Understanding these principles is key to interpreting mass spectra.