Periodic Trends and Atomic Properties (4E) Practice Test

A mass spectrometry workflow ionizes neutral atoms (gas phase) before detection. For a calibration set, the instrument uses elements from Period 3: Na, Mg, Al, Si, P, S, Cl. If all are isolated neutral atoms, which element would most likely require the least energy to remove one electron (lowest first ionization energy), based on periodic trends and electron configuration effects?

A medicinal chemistry group is tuning the polarity of a covalent bond in a prodrug to optimize hydrolysis in aqueous buffer. They consider single bonds between carbon and one of the following atoms: F, O, N, or Cl. Assuming comparable bonding environments, which atom would most likely produce the most polarized C–X bond (largest partial negative charge on X) based on periodic electronegativity trends?