Topic 4 Structures Flashcards
Give 4 properties of Giant Ionic Lattices?
Crystalline
High Melting and Boiling Point
Conducts electricity when liquid, molten or dissolved in water
Soluble in water
Why do Giant Ionic Lattices have such high melting and boiling points?
The ionic bonds are very strong, and bond breaking is an endothermic reaction therefore lots of heat/energy is required to break these bonds
Why do Giant Ionic Lattices conduct electricity when molten, liquid or dissolved in water?
The attractions between the ions are overcome, allowing ions to move freely and carry current
Give 4 properties of Simple Covalent structures?
Low melting and boiling point
Don’t conduct electricity
Not soluble in water
Soft when solid
Why do Simple Covalent structures have low melting and boiling points?
The Van Der Waal forces between the simple covalent molecules are very weak, meaning very little heat/energy is required to depart the molecules
Why don’t Simple Covalent Molecules conduct electricity?
There are no free electrons and molecules don’t have any charges
Give 3 examples of Simple Covalent Structures?
Chlorine
Carbon Dioxide
Water
What is an allotrope?
Different form of same element in same physical state
Give 2 allotropes that are Giant Covalent Molecules?
Diamond
Graphite
Give 4 properties of Diamond?
Very high melting and boiling point
Doesn’t conduct electricity
Insoluble in water
Extremely hard solid
Give 4 properties of Graphite?
Very high melting and boiling point
Conducts electricity
Insoluble in water
Slippery soft solid
Why doesn’t diamond conduct electricity?
No free electrons or ions to carry charge
Why does Diamond have such high melting and boiling point?
The carbon atoms in diamond are held together by very strong covalent bonds
Why does Graphite conduct electricity?
There are delocalised electrons between the layers of graphite so current can be carried by these electrons
Why is Graphite so soft and slippery?
Th weak Van Der Waal Forces between the layers of Graphite allow the layers to slide over each other
Why does Graohite have such a high melting and boiling point?
Although the Van Der Waal forces between the layers are very weak, the string covalent bonds in the hexagonal layers are extremely difficult to break
Give one use of Diamond?
Diamond can be used for cutting tools, such as glass cutters or drill bits
Give one use of Graphite?
Graphite can be used as a lubricant, as the layers are able to slide over each other making it very soft and slippery. This lubricant can be used on machinery
Give 5 properties of Metallic Structures?
High Melting Point and Boiling Point Dense and Strong Conducts heat and electricity Malleable Ductile
Why do Meatllic Structures conduct electricity?
The delocalised electrons can move freely and can carry current
Why do Metallic Structures have such high melting and boiling points?
The strong bond between positive metal ions and negative delocalised electrons is very hard to break, although in some metals can be
relatively weak, such as in Potassium or Sodium
Why are Metallic Structures Malleable and Ductile?
The layers can slide over each other when force is applied, also delocalised electrons move between the metal ions and hold together the structure when bent or stretched
Give 2 uses of Aluminium?
Overhead electrical wiring
Alloys for aircraft
Give 4 uses of copper?
Electrical wiring
Plumbing
Brass
Coinage
