Chapter 3 - Structure and bonding Flashcards
What happens during ionic bonding?
atoms gain or loose electrons to form charged particles called ions to get a full outer shell
Magnesium oxide
Mg 2+ O 2-
Calcium chloride
Ca 2 + Cl - Cl -
Ionic compounds have…
- lattice structure
- regular arrangement
- strong electrostatic forces
- high melting/boiling points
- conduct electricity when dissolved or molten
which groups are most likely to form ions?
groups 1&7 and groups 2&6
What happens during covalent bonding?
atoms share electron to gain a full outer shell
examples of covalent bonding
NH3, CH4, HCl, CO2, H2O, F2, Cl2
what is the boiling/melting point of an ionic compound like?
High! - strong electrostatic forces, takes a lot of energy to separate ions
whats the melting/boiling point of a small covalent compound?
low! - weak intermolecular forces, molecules can be separated easily
simple molecular covalent substance properties
- strong bonds
- weak forces of attraction
- low melting and boiling points
- does not conduct electricity
An two examples of a giant covalent structure and its properties
Graphite and Diamond
- strong bonds
- high melting and boiling points
- do not conduct electricity
properties of diamond
all covalent bonds are identical
a form of carbon
each carbon atom is joined to 4 other carbon atoms - making it a giant covalent structure
properties of graphite
layers of carbon atoms bonded to only 3 other carbons
hexagon shapes
delocalised atoms between layers - layers can slide
metalic bonding
delocalised and free-moving atoms - structure inside metals
good conductors of heat
regular pattern
flexible
what is a smart alloy?
a type of smart material that can remember and return to its original shape after being heated
