Question

26 multiple choice 1 point
what is the energy change that occurs when an electron is added to an atom called?
○ ion
○ second ionization energy
○ electron affinity
○ first ionization energy
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27 multiple choice 1 point
which russian scientist created such a comprehensive periodic table that he was able to predict elements that had not yet been discovered?
○ meye
○ mendeleev
○ moseley
○ bohr
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Explanation:

Question 26

• "ion" is a charged atom/molecule, not energy change.
• "second ionization energy" is energy to remove a second electron.
• "electron affinity" is the energy change when an electron is added to an atom.
• "first ionization energy" is energy to remove the first electron.

• Dmitri Mendeleev created the periodic table that predicted undiscovered elements. Meyer, Moseley, and Bohr had other contributions (Meyer: periodic table, Moseley: atomic number, Bohr: atomic model).

Answer:

C. electron affinity

Question 27