Structures Flashcards
What is a giant ionic lattice
Regular arrangement of alternating positive and negative ions
Examples of giant ionic lattice
Sodium chloride
Magnesium oxide
Properties of a giant ionic lattice
Crystalline
High melting points
Conducts electricity when liquid
Doesn’t conduct electricity when solid
Soluble in water
Why is a giant ionic lattice got high melting points
Ionic bonds are strong and require a lot of energy to break therefore it has a high melting point.
Why does a giant ionic lattice conduct electricity when a liquid but not when a solid
It doesn’t conduct electricity when a solid because ions are not free to move and carry charge, the ions are free to move and carry charge when liquid therefore able to conduct electricity.
What properties does a covalent molecular have
Low melting and boiling points
Doesn’t conduct electricity,
Not soluble in water
Soft when solid
Why does a covalent molecular have low melting and boiling points
Due to weak bonds between molecules breaking easily as requires little energy to break
Why does a covalent molecular not conduct electricity
No charged particles that are free to move and carry charge
Why is a covalent molecular soft when solid
Due to the weak bond between molecules breaking easily
What is the name of the forces between the molecules in simple covalent structures
Van Der Waals
Examples of a covalent molecular
Iodine
Carbon dioxide
Water
Ammonia
Methane
What is Giant covalent DIAMOND
Extensive covalent bonding in all directions with each carbon bonded to 4 others in a tetrahedral arrangement
What might the giant covalent DIAMOND be used for
Used in drill bits
Features of the giant covalent bond DIAMOND
Very high melting and boiling points
Diamond doesn’t conduct electricity
Insoluble in water
Diamond is extremely hard
Why does the giant covalent DIAMOND have very high melting and boiling points
Due to strong covalent bonds requiring large amounts of energy to break
Why does the giant covalent DIAMOND not conduct electricity
No charged particles free to move and carry charge
Why is the giant covalent DIAMOND very hard
Due to the extensive strong covalent bonds
What is the giant covalent GRAPHITE
Layered structure with each carbon bonded to 3 others in the layer
What might the giant covalent GRAPHITE be used in
Lubricant and pencil led
There is ….. free electron per each carbon atom which becomes delocalised in the giant covalent
One
The giant covalent GRAPHITE has weak ….
Van der waals between layers
Describe the giant covalent graphite
A slippery soft solid as weak van der waals between layers allows the layers to slide over each other
Properties of the giant covalents graphite and graphene
Conducts electricity as they have delocalised electrons free to move and carry charge
Giant covalent Graphene properties
Conducts heat and electricity efficiently
Nearly transparent
100x stronger then steel
Very thin
Light
Inexpensive
What is might the giant covalent Graphene be used for
Solar cells, light emitting diodes, touch panels, smart windows or phones
Describe the giant covalent GRAPHENE
It is a single atom thick layer of graphite with strong covalent bonds between each carbon atom. The atoms are arranged in hexagons / two dimensional
What is a giant metallic structure
Regular arrangement of closed packed metal ions in a sea of delocalised electrons
Properties of a giant metallic structure
High melting points
Dense and strong
Conducts electricity
Conducts heat
Ductile
Malleable
Why does a giant metallic structure have a high melting point and is strong and dense
Strong metallic bonds require a lot of energy to break
How can a giant metallic structure conduct electricity
Free delocalised electrons are free to move and carry charge
Why is a giant metallic structure ductile and malleable
Can be reshaped without falling apart as metal ions slide over each other and are still held in place by delocalised electrons
Why does a giant metallic structure conduct heat
Free elections with high kinetic energy can move around and transfer particles.
What is an alloy
A mixture of two or more elements at least one of which is metal, and the resulting mixture has metallic properties
Example of alloys
Steel is a alloy of IRON + CARBON
white gold is a alloy of SILVER + GOLD
rose gold is a alloy of GOLD + COPPER
brass is a alloy of ZINC + COPPER
What unit is used to measure the percentage of gold in alloys
Carats
How to find the percentage of gold in a alloy
Number of carats ➗ 24 ✖️ 100
What are allotropes
Different forms of the same element in the same physical state
Ductile meaning
Can be drawn into wires
Malleable
Can be hammered into shape
Metallic bonding Meaning
The attraction between delocalised electrons and positive ions in a regular lattice
