AP Chemistry: Atomic Structure and Mass Spectrometry

Flashcards covering key AP Chemistry concepts including stoichiometry, mass spectrometry interpretations, isotopic abundances, and molar mass calculations.

Oxide Mass Fraction of Oxygen

Among metal oxides containing one oxygen atom per formula unit, a $1.00\,g$ sample of $MgO$ contains the greatest mass of oxygen because $MgO$ has the smallest molar mass ($40.3\,g$) compared to $Na_2O$ ($62.0\,g$), $CaO$ ($56.1\,g$), and $K_2O$ ($94.2\,g$).

Mass Spectrum of Antimony ($Sb$)

A mass spectrum characterized by two primary isotopic peaks located at $121\,amu$ and $123\,amu$, which together produce an average atomic mass of approximately $121.76\,amu$ for $Sb$.

Mass Spectrum of Zirconium ($Zr$)

A mass spectrum showing a major peak at $90\,amu$ alongside smaller peaks at $91\,amu$, $92\,amu$, $94\,amu$, and $96\,amu$, resulting in a weighted average atomic mass that identifies the element as $Zr$.

Mass Spectrum of Molybdenum ($Mo$)

A mass spectrum displaying multiple isotopic peaks across $92\,amu$ to $100\,amu$ with an approximate weighted average atomic mass of $96\,amu$, identifying the element as $Mo$.

Peak at $26\,amu$ in Magnesium ($Mg$) Mass Spectrum

A peak representing an isotope of magnesium containing 12 protons and 14 neutrons ($^{26}Mg$), in an element sample whose overall average atomic mass is closest to $24\,amu$.

Mass Spectrometry

An experimental technique used to determine the isotopic composition of an element by measuring the mass-to-charge ratio and relative abundance of its isotopes.

Average Atomic Mass

The weighted average mass of all naturally occurring isotopes of an element, calculated based on the relative abundance and isotopic mass of each isotope.