atomic structure and isotopes Flashcards
what is electrostatic attraction
The positively charged protons in the nucleus attract the negatively charged electrons in the electrons shells
what is the charge of an atom
0
how are ions formed
when atoms either gain or lose electrons, causing them to be charged
what is the atomic number
the number of protons in an atom
how do you work out mass number
number of protons + number of neutron
what is an isotope
atoms of the same element that contain the same number of protons and electrons but a different number of neutrons
what are chemical properties of an isotope
-Isotopes of the same element display the same chemical characteristics, because they have the same number of electrons in their outer shells
what determines the chemistry of an atom
Electrons take part in chemical reactions and therefore determine the chemistry of an atom
what are physical properties of an isotope
different number of neutrons, same number of protons
- as neutrons only add mass and density to the atom
what does a mass spectrometer measure
The percentage abundance of the isotopes in an element
stages of spectrometery
vaporisation
ionisation
acceleration
deflection
detection
what happens in the vaporisation stage in mass spectrometery
the sample is vaporised
what happens in the ionisation stage in mass spectrometery
the sample is ionised to form positive ions
what happens in the acceleration stage in mass spectrometery
the ions are accelerated
what happens in the deflection stage in mass spectrometery
heavy ions move slower and are deflected
what happens in the detection stage in mass spectrometery
the ions are detected as a mass-to-cherge ratio, written as m/z
what can the mass spectra produced be used to calculate
the relative atomic mass of an element and its isotopes
what is relative isotopic mass
the mass of an atom of an isotope compared with 1/12th of the mass of carbon 12
what is relative atomic mass
weighted mean mass of an element compared with 1/12th of the mass of an atom of carbon 12
what is relative molecular mass
weighted mean mass of a molecule compared with 1/12th of the mass of an atom of carbon 12
relative formula mass
weighted mean mass of a formula unit compared with 1/12th of the mass of an atom of carbon 12
