Ionic Compounds Flashcards
Name this complex ion and give its valency
NH4
ammonium ion
valency 1+
This is the CO3 complex ion. State its name and valency
Carbonate ion
valency 2-
What is the valency of a zinc ion?
Zn 2+
What is the formula of calcium fluoride?
CaF2
Ca is in group 2 - has valency of 2+
F is in group 7 - has valency of 1-
Use cross and drop….
What is the formula of magnesium oxide?
MgO
Mg is in group 2 - has valency of 2+
O is in group 2 - has valency of 2-
Use cross and drop…. anc cancel down to simplest ratio
Explain in terms of electrons how Na and O react to form sodium oxide
Two Na ions lose one electron each to form 2 Na+ ions
One oxygen atom gain these 2 electrons to form O2-
2[Na+] O2-
Na2O
Why do both metals and molten ionic compounds conduct electricity?
Both have charge particles which are free to move and carry charge
But, metals have negatively charge electrons which can carry charge and molten ionic compound have both postive and negative ions which can carry charge.
What are the two possible copper ions?
Cu 1+ and Cu 2+
Draw a cross dot diagram from Magnesium fluoride

Calcium loses two electrons to become Ca2+.
Is calcium oxidised or reduced?
oxidised
OIL RIG
Oxidation is loss of electrons
Draw the dot cross diagram for sodium oxide
remeber to use square brackets and to write in the charge of the ions

Draw the structure of an ionic compound
Alternating + and - ions in a giant (3D) lattice structure

Explain in terms of electrons how Mg and Cl react to form Magnesium chloride
Mg loses 2 electrons to form Mg2+
Two Cl atoms gain one electron each to form two Cl- ions
Mg2+ 2 [Cl1-]
Why is an ionic compound soluble in water but not soluble in an organic solvent?
Ionic compounds consist of charged ions and water molecules are polar (have charged ends on the molecule) this forms electrostatic attraction which can pull ionic compounds apart making them dissolve or dissociate
organic solvents do not have polar molecules (or molecules with charged ends) so they cannot attract and pull apart the ions in ionic compounds.
Draw a dot cross diagram for Magnesium oxide

What is the valency of the hydroxide ion
OH 1-
What is oxidation?
When an atom loses electrons OR gains oxygen
K1+ - potassium lost one electron
MgO - magnsium has gained oxygen
What is the formula of sodium nitride?
Na3N
Na is in group 1 - has valency of 1+
N is in group 5 - has valency of 3-
Use cross and drop….
Describe how electron shielding makes elements like potassium more reactive than lithium.

Potassium is a large atom
Potassium has more electrons (more electron shielding) between the nucleus and outer electrons and therefore has more repulsion on the outer electrons
The outer electron in potassium requires less energy to be remove
Therefore potassium is more reactive than lithium
Why is the melting point of MgO higher than the melting point of NaCl?
Mg ion has a charge of 2+ and oxygen ion has a charge of 2-
Na ion has a charge of 1+ and chloride ion has a charge of 1-
The ions in MgO have double the charge and therefore have a much greater electrostatic force of attraction
This requires more energy to overcome the ionic bonds in MgO than in NaCl
Why do metals and ionic compounds both have high melting points?
They both have many strong bonds in a giant structure
which requires a lot of energy to overcome
Fluorine atom gains an electron to become F1-.
Is fluorine oxidised or reduced?
reduced
OIL RIG
Reduction is gain of electrons
Name the complex ion and give its valency
OH
hydroxide ion
OH 1-
What is the difference between an ionic bond and a metallic bond?
both electrostatic attraction
both giant structure with many bonds
Both contain metal ions
BUT
Metallic is the attraction between a metal ions and delocalised electrons
Ionic is the attaction betwen a metal ion and a negative ion (or oppositely charge ions)



