GR 10 Review + 1.7 + 3.4 [UNIT 1] Flashcards
Atomic Radius and Trend (and why?)
The size of the atom from the nucleus to the outermost electron. Measured in picometres (pm).
Left to right = Decreases (across a period) because there are more protons as you go left to right so there is more pull of the electrons, decreasing the radius between the nucleus and the outermost electron.
Up to down = Increases (across a group) because there are more electrons so there are more energy shells, increasing the radius between the nucleus and the outermost electron.
Metal ions will always be smaller than their atomic counterparts (due to losing electrons).
Non-metal ions will always be bigger than their atomic counterparts (due to gaining electrons).
Ionization Energy and Trend (and why?)
also what’s the eqn. for it?
The amount of energy required for an atom in gas state to lose an electron and become an ion (cation). Measured in kilojoules (kJ).
Left to right = Increases (across a period) because there are more protons so there is more pull of the electrons, so it’s harder to remove and requires MORE ENERGY (so ionization energy INCREASES)
Up to down = Decreases (across a group) because there are more shells so it is easier to gain/lose electrons
Ionization Energy: X(g) + energy > X+ (g) + e-
Electron Affinity and Trend
also what’s the eqn. for it?
The energy released when an atom gains an electron. Measured in kilojoules (kJ).
Left to right = Increases (across a period)
Up to down = Decreases (across a group)
Electron Affinity: X(g) + e- > X- (g) + energy
Electronegativity and Trend
The tendency/ability of an atom to gain electrons (become an anion).
Left to right = Increases (across a period)
Up to down = Decreases (across a group)
What two things do noble gases not have? (probs very important to know)
Electron affinity because they don’t gain electrons, so no energy change.
And electronegativity because there is no need for them to gain electrons.
