The average mass of an atom of an element relative of an atom of Carbon -12.
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What is the definition of relative isotopic mass?
The mass of an atom of an isotope of an element relative of an atom of Carbon -12.
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What is the definition of relative molecular mass?
The average mass of a molecule on a scale where an atom of Carbon 12 is 12.
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How do you work out the relative atomic mass?
Multiply the % relative isotopic abundance by the relative isotopic mass. Add up all the totals. Divide by 100.
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What is the definition of the first ionisation energy?
The energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions
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What is an equation for the first ionisation energy of oxygen?
O(g) -> O+ + e-
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What are the 3 factors affecting ionisation energy?
Nuclear Charge, Distance from the nucleus and shielding
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What is meant by a high ionisation energy?
There is a high attraction between the electron and the nucleus and so more energy is needed to remove the electron
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What is the definition of the second ionisation energy?
The energy that is needed to remove 1 electron from each ion in 1 mole of gaseous 1+ ions to from 1 mole of gaseous 2+ ions
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What is an equation for the second ionisation energy of oxygen?
O+ -> O2+ + e-
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What is the effect of nuclear charge on first ionisation energy?
The more protons that there are in an element, the stronger the attraction is, meaning the electrons are harder to remove and require a higher amount of energy
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What causes the sudden increases in ionisation energy?
When a new shell is broken into
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What is the trend of first ionisation energies down a group?
They decrease
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What is the trend of first ionisation energies across a period?
They increase (generally)
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Why do ionisation energies decrease down group 2?
Each element has an extra energy shell to the previous element. This measn that there is extra shielding and therefore less attraction making the electron easier to remove or the extra shell is further away and less attracted.
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Why do ionisation energies increase across period 3?
The number of protons are increasing - there is more attraction.
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Why is there a drop between groups 2 and 3 for ionisation energy?
The electrons are on a different sub shell with a slightly higher energy, so is further away from the nucleus.
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Why is there a drop between groups 5 and 6 for ionisation energy?
Electron repulsion - if an electron is being removed from a singly occupied orbital it is harder to remove because there is no repulsion between electrons compared to if it was a full orbital.
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What are the 4 steps in the mass spectrometry
Ionisation, Acceleration, Ion Drift and Detection
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Other cards in this set
Card 2
Front
What is the definition of relative isotopic mass?
Back
The mass of an atom of an isotope of an element relative of an atom of Carbon -12.
Card 3
Front
What is the definition of relative molecular mass?
Back
Card 4
Front
How do you work out the relative atomic mass?
Back
Card 5
Front
What is the definition of the first ionisation energy?
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