Electrons - pt. 2 Flashcards
What is the box method of electron notation?
use a box to indicate the orbital
use 2 arrows to indicate the electrons in each orbital - one up, one down to indicate opposing spins
What is spectroscopic notation?
if there are 2 electrons in the first s orbital it is written like this:
1s^2
e.g.
Na - 1s^2 2s^2 2p^6 3s^1
you can start with the noble gas that comes before it
e.g. S - [Ne] 3s^2 3p^4
What do atoms prefer? How does this affect chromium and copper?
to have a filled or half filled sub shells, rather than 4 or 9 electrons in a shell of 10
chromium and copper move a electron away from the 4s orbital to 3d to fill/half fill that sublevel
4s becomes higher energy for some transition metals
What is the first ionisation energy?
energy required to remove ONE MOLE of electrons from ONE MOLE of atoms in the gaseous state
What is the equation for the first ionisation energy?
M(g) -> M^+(g) + e^-
the first IE is always this even if the ion formed is 2+ or 3+
the units are kilojoules per mole
Why is the reaction endothermic?
energy is required
What happens to IE from Na to Mg and why?
Mg has a full 3s orbital, and a larger nuclear charge than Na, therefore it increases
What happens to IE from Mg to Al
the outermost electron in Al occupies the 3s orbital, which is further from the nucleus than the outermost electron in 3d, as a result the force of attraction on the electron is smaller
therefore IE drops
What happens to IE from Al to Ar?
continues to rise because nuclear charge increases
although, it stays the same between the P and S because of electron pair repulsion
What are the anomalies?
when an element enters a different orbital across a period, first IE decreases because distance increases
when you get a pair in a orbital their is a dip because of electron pair repulsion
Why is there an increase in IE after each electron is removed?
the ion becomes increasingly charged and force of attraction increases
Why does IE decrease down the group in group 2?
electrons get more distant from the nucleus so less energy is required to remove them
Why does IE decrease down a group?
despite nuclear charge increasing, IE decreases
the positive charge attracting the electron in the outer shell is less than the full nuclear charge
this is because of the effect of inner electrons shielding the nuclear charge
