Lecture 5/6-The Electronic Configuration Of The Atom Flashcards
Where are e- in an atom?
In stable energy levels
What does the absorbtion of a photon of light do?
Allow the e- to jump to a higher level
What does the jumping down of an e- to a lower level do?
Emits a photon of light
If you measure the energy of the photon that has jumped up + down, what will you find?
The energy difference between levels (they are not evenly spaced)
What is 1st ionisation energies?
The energy required to remove 1 mole of e- from 1 mole of gaseous atoms to form one mole of positive ions
Why are ionization energies positive?
Energy must be put into the system to pull the negative e- away from the positive protons
Why does higher nuclear charge have a higher ionization energy?
Because there is a greater pull of the nucleus on the e-
What is e- affinity?
The energy required to add 1 mole of e- to 1 mole of gaseous atoms to form 1 mole of gaseous negative ions
Cl-(g) + e- —> Cl-(g)
E- affintiy
The more negative the e- affinity the ……
more STABLE the negative ion
Why is the 2nd e- affinity positive?
Because energy needs to be put in to add e- to a negative ion
Atomic size trends
Increases down a group
Decreases across a period
1st Ionization energy trends
Decrease down the group
Increase across a period
1st E- affinity trends
Less negative down a group
More negative across a period
What are orbitals?
Regions in space where there’s a 95% probability finding a particular e-
What does the quantum number n indicate
- The distance of an e- from the nucleus
- The energy of an e-
- Number of e- a shell can hold
The higher the quantum number n the?
The further away from the nucleus the e- is