1.2.2 and 1.2.3 - Isotopes and Mass Spectra Flashcards
What are isotopes?
atoms of the same element with different numbers of neutrons
What can different masses of isotopes lead to?
different physical properties like boiling and melting points
What makes a nucleus radioactive?
it contains either too many or too few neutrons to be stable
How does a radioactive neucleus change to become more stable?
by emitting radiation
Why are radioisotopes useful in tracking movement of elements or compounds?
because the emitted radioactivity can be detected
What are mass spectra used to do?
determine the relative atomic masses of elements from their isotopic composition
What does a mass spectrometer measure?
the mass and abundance of isotopes
What is the mass/charge ratio?
the mass when the ions have a single positive charge
How are fragmentation patterns formed?
when a compound is analyzed in a mass spectrometer, the electron collisions during ionization are so energetic that they cause the molecule to break up into fragments
What do fragmentation patterns provide?
useful evidence about the structure of the compound
What agreed standard are masses of atoms measured relative to?
carbon-12
What are the results of the analysis by a mass spectrometer presented in the form of?
a mass spectrum
What is displayed on the horizontal axis of the mass spectrum?
the mass charge ratio, although it is generally just the mass because the charge is usually +1
What is displayed on the vertical axis of a mass spectrum?
the relative abundance of the ions corresponding to different isotopes
