Structure 2.1 Flashcards
What are cations formed from?
Low ionisation energy elements
Anions
Non-metals gaining electrons to form a full outer shell
Isoelectric
Two different species with the same electron configuration
Transition element
Element with a partially filled d subshell
What is special about transition elements?
It can form multiple ions with different charges
Ionic bond
Sum of all of the electrostatic attractive and repulsive forces between ions in the lattice
Lattice enthalpy value tells you what?
How strong the ionic bonds are in a particular ionic lattice
The smaller the ion, the ___ of the lattice enthalpy
The greater the lattice enthalpy
The greater the charge, the ___ of the lattice enthalpy
The greater the lattice enthalpy
Properties of ionic compounds
High melting and boiling points, electrical conductivity, solubility
Why do ionic compounds have high melting and boiling points?
They have strong electrostatic forces which require high energy to overcome
Ionic compound’s electrical conductivity
In the solid state, don’t conduct as no free electrons and ions are in fixed positions. In molten state, they are electrolytes (no free electrons but mobile ions carry charge) so can conduct but decompose chemically when they do so.
Ionic compounds solubility
Most ionic compounds are soluble in water. Water makes compounds hydrated (exothermic reaction) and if this energy is greater than the lattice enthalpy, the salt dissolves in water and lattice can be broken by sufficient energy
Polyatomic ions
Are ions that consist of two or more atoms bonded together with covalent bonds
