Topic 3 Bonding Flashcards
What is an ion
An ion is a atom that has lost or gained electrons
What is a cation
A positively charged ion
What is an anion
A negatively charged ion
how to write ionic formulae
balance the charges
what group have full outer shells
the noble gasses
ionic bond:
a bond formed bt the electrostatic attraction between opposing charges
properties of ionic bonding
organised in a lattice structure with both a positive metal ion and a negative non metal ion. held together by an electrostatic force
properties of metalic bonding
delocalised electrons and positivley charged metal ions
what happens when a force is applied to a metalic bond
the ions are free to move over one another
why do metalic bonds have a high bp and mp
rhere are stong electtrostatic forces of attraction between the metal cations and delocalised electrons
what are covalent bonds
when 2 non metals react both wanting full outer shells
how many covalent bonds do carbon and hydrogen form
4
Simple covalent structures
They have low melting points as there are weak intermolecular forces between the molecules that are easy to break down. Cannot conduct electricity
Giant covalent substances
Substances with giant covalent structures are solids with very high melting points. All the atoms are linked by strong covalent bonds, which must be broken to melt the substance. Examples are diamond, graphite. Generally do not conduct electricity
Allotropes
Different structural. Forms of the same element
