1.1 Atomic Structure Flashcards
What is the mass number?
The total number of protons and neutrons
What is the proton number?
The number of protons
What is an ion?
An atom which has gained or lost an electron
What is an isotope?
An atom with the same number of protons and electrons but different neutrons. The same chemical properties.
What is the relative atomic mass?
The average mass of an atom of an element, taking into account its isotopes, relative to 1/12th the relative atomic mass of an atom of Carbon 12
What is the relative molecular mass?
The mass of a molecule compared to 1/12th the relative atomic mass of an atom of Carbon 12
What is the relative isotopic mass?
The mass of an atom of an isotope relative to 1/12th of carbon 12.
What type of mass spectrometer are we using?
Time of Flight
What is electrospray ionisation?
A sample dissolved in a polar solvent is pushed through at a high pressure and ionised by a high voltage.
What is the acceleration stage?
The ions are accelerated by a magnetic field. Lighter ions experience more speed.
What is ion drift?
Ions drift through a vacuum region with equal kinetic energy as they leave the magnetic field. The lower mass/charge ration travel faster as they are lighter.
What is the detection stage?
Ions hit the detector, receive an electron and the current is recorded to produce a mass spectra
What are the four orbitals?
s,p,d,f
What is the first ionisation energy?
The energy required to remove 1 electron in 1 mole of gaseous atoms to form 1 mole of gaseous ions
How does atomic radius affect ionisation energy?
The greater the atomic radius, the smaller the nuclear attraction experienced by outer electrons
How does nuclear charge affect ionisation energy?
The more protons that there are, the bigger the positive charge and attraction on the outer electron
How does shielding affect ionisation energy?
The inner shells of electrons repel the outer shells of electrons
How do you write an equation for successive ionisation energies?
Li (g) -> Li + (g) + 1 e-
What is special between the 4s and 3d orbitals?
They are sol similar in energy that 4s fills before 3d and sometimes half shells are filled to create even numbers.
Why do we ionise our sample in Mass Spectroscoper?
So the sample has an overall charge so can be manipulated by a magnetic field to speed up in accelleration phase.
