Ionic bond

sodium chloride NaCl table salt sodium bicarbonate NaHCO3 baking soda sodium hydroxide NaOH lye drain cleaner magnesium sulfate MgSO4 Epsom salt sodium hypochlorite NaOCI bleach

Atoms of elements tend to combine in such a way that they have eight electrons in their outermost/valence electron shell (two electrons for period 1 elements), giving them the same electron arrangement as a noble gas (octet structure).

They achieve this by either transferring electrons or sharing electrons

Metal atoms lose electrons to become cations (positive ions).

Non-metal atoms gain electrons to become anions (negative ions).

The number of electrons lost or gained is determined by the electron configuration of the atom.

The positively and negatively charged ions are held together in a giant lattice

It is a regular 3D arrangement with infinite ions - formed by many strong ionic bonds.

Strong electrostatic force of attractions between oppositely charged ions.

● When naming an ionic compound, cation should be named first and followed by anion. ● No prefix needed to indicate the number of ions in the compound. ● The charge of transition metal cations (several possible charges) should be shown as a roman numeral in a bracket.

(a) type of structure, (b) the type of constituent species, and (c) the type (the strength) of attraction between constituent species

● Ionic compounds are solids under ambient conditions (25 °C and 1 atm). ● Strong electrostatic force of attractions between the oppositely charged ions (ionic bond) in its lattice ● Large amount of heat energy is required to break the many strong bonds.

Tendency of a substance to vaporize.

Ionic compounds are considered as being non-volatile ○ large amount of energy needed to break the strong ionic bonds in lattice

brittle and hard If layers of ions slip against each other, ions with the same charge come up against each other – like charges repel and break up the crystal

Movement of charges (e.g. electrons, ions) is needed to conduct electricity. ● Solid ionic compounds do not conduct electricity - ions are held firmly (fixed) in the lattice. ● Molten/ liquid ionic compounds conduct electricity. ● Mobile ions move to conduct electricity ● Aqueous ionic compounds (dissolved in water) conduct electricity. ● Mobile ions move to conduct electricity.

All compounds with group 1 metal ions (e.g. Na+, K+) and ammonium ions (NH4+) are soluble.

All nitrates (NO3-) and hydrogencarbonates (HCO3-) are soluble.

All carbonates (CO32-) and phosphates (PO43-) are insoluble except those mentioned in (1), group 1 metal ions

All hydroxides (OH-) are insoluble except those mentioned in (1), Ba(OH)2and Ca(OH)2 (sparingly soluble). It is an aqueous solution when it is in the form of limewater. However, when it is formed during reactions, it exists as an insoluble compound.

All sulphates (SO42-) are soluble except CaSO4 , BaSO4 , PbSO4 , Ag2SO4 .

All halides (Cl-, Br-, I-, general form: X-) are soluble except PbX2 and AgX.

Equations that only show the chemical species that have participated in the reaction (such as ions and molecules).

Ions that are chemically unchanged for the entire process are called spectator ions - they can be removed from the equation.