Ionisation energies/ionic bonding Flashcards
what is ionisation energy?
it is the energy required to remove one electron from each atom in a mole of gaseous atoms, producing one mole of 1+ gaseous ions
what is 2nd ionisation energy?
is the energy required to remove the second electron
what are the three factors affecting the ionisation energy?
-Distance from nucleus
-nuclear charge
-shielding
What are the four subshells?
s,p,d,f
what is the maximum number of electrons? in 2,p,d,f
s=2
p=6
d=10
f=14
The distribution of sub-shells across the first four shells is as follows:
Shell Sub-shells Total number of electrons
1 1s 2
2 2s, 2p 8
3 3s, 3p, 3d 18
4 4s, 4p, 4d, 4f 32
what is electron configuration?
The arrangement of electrons in an atom
what two ways can electron configuration be depicted?
-Sub-shell notation
- Electrons-in-boxes notation
describe what is Electrons-in-boxes notation?
Orbitals are depicted as boxes, with electrons shown as arrows.
Oppositely directed arrows represent electrons with opposite spins.
Electron pairing within orbitals occurs only with opposite spins.
describe what is Sub-shell notation?
This method uses superscripts to indicate the number of electrons within each sub-shell.
For example, the electron configuration of neon (10 electrons) is 1s2 2s2 2p6.
in electron configuration why is the 4s orbital filled before the 3d sub-shell?
The 4s sub-shell is filled before the 3d sub-shell because the 4s orbital has a lower energy than the 3d orbitals in neutral atoms.
Chromium (Cr) and copper (Cu) exhibit unusual electron configurations:
Cr: 1s2 2s2 2p6 3s2 3p6 3d5 4s1 (instead of 3d4 4s2)
Cu: 1s2 2s2 2p6 3s2 3p6 3d10 4s1 (rather than 3d9 4s2) why?
These exceptions occur because configurations with a half-filled (d5) or fully filled (d10) d sub-shell are energetically more favourable.
how to work out the last part of the electronic structure of a element?
e.g li is 2s1
2 is the period lithium is in
s is the block lithium is in
1 is the number in the group
what are the block the element is in?
-the transition metals are all block D
-the elements on the left hand side of the metals are the S block including hydrogen and helium
-the elements on the right hand side of the metals are the P block
-elements on the bottom two rows are the F block
Metal atoms lose electrons to become positive ions called?
cations
Non-metal atoms gain electrons to become negative ions called?
anions
what happens in ionic bonding?
In ionic bonding, electrons lost by the metal atom are transferred to the non-metal atom. This transfer allows both atoms to achieve full outer electron shells, resulting in the formation of stable ions.
transition metals can form multiple ions with different charges, why?
transition elements have partially filled d sub-shells
3d and 4s sub-shells allow for successive ionisations in many transition elements, resulting in the formation of ions with varying charges. why?
due to the similar energies of the 3d and 4s sub-shells
what is the chemical formular of a nitrate ion?
Nitrate ion (NO3-)
what is the chemical formular of a carbonate ion?
Carbonate ion (CO3 2-)
what is the chemical formular of a sulphate ion?
Sulfate ion (SO4 2-)
what is the chemical formular of a hydroxide ion?
Hydroxide ion (OH-)
what is the chemical formular of a Ammonium ion?
Ammonium ion (NH4+)
An ionic bond is the what type of force of attraction between oppositely charged ions, usually a metal and a non-metal.?
electrostatic force
are electrostatic bonds very strong?
yes
Key features of a giant ionic lattice:
-Each ion is electrostatically attracted to ions of the opposite charge in all directions.
-It takes significant energy to overcome these strong electrostatic forces between the ions.
Properties related to ionic structure?
-High melting and boiling points - The strong electrostatic attractions between the positive and negative ions in the giant lattice must be overcome for the lattice to break apart; this requires a lot of energy.
-Conduct electricity when molten or in solution - When melted or dissolved, the ions can move freely and carry electric charge through the liquid.
-Do not conduct electricity as solids - In the solid lattice structure, the ions are firmly locked in place and unable to move to carry electric charge.
-Dissolve in water - Water molecules, which are polar, attract the charged ions in the lattice via ion-dipole forces, pulling them away from the lattice and dissolving the structure.
