Bonding And Structure Flashcards
Explain ionic bonding
In order for an atom to have a complete outer shell it needs to gain or lose an electron.
Ionic compounds are created when atoms react trying to gain a full outer shell
What are the properties of an ionic compound (and why)
high melting and boiling point because the strong attraction between the ions needs a lot of energy to break
soluble in water because the charges on the ions attract the charges on the water molecules, which allows the ions to be pulled apart and surrounded by water
They conduct electricity when molten or dissolve because the ions are free to move around and carry electric charge
What are simple molecular substances?
A few atoms held together by covalent bonds
What is covalent bonding
When atoms bond because they want to have a full outer shell, they share electrons
Diamond
Is a giant covalent structure that is an allotrope of carbon. each carbon in diamond is covalently bonded to four other carbon atoms. All of the outer shell electrons in carbon are involved in the bonding.
Graphite
Graphite is a giant covalent structure that is an allotrope of carbon.
The carbon atoms are arranged in layers with each carbon atom bonded to three of the carbon atoms by strong covalent bonds.
Each atom has one electron and its out of shell that is not involved in bonding and is a free electron. layers have weak bonding between them.
Uses of graphite
Conduct electricity because three electrons from each layer has dislocated electrons that carry charge
Used in pencils, electrodes, lubricants
Uses of diamond
Diamond issues for drill, tips, jewelry, and a glass cutting
Buckminsterfullerine
Carbon atoms form the shape of a ball with a carbon atom at each corner of the 20 hexagon and 12 pentagons
Used for a catalyst for lubricant nano tubes for strengthening and delivering drugs
Carbon nanotubes
Conduct electricity because free moving electrons can travel quickly up the nano tube with nothing blocking their path
Metallic bonding
The way that metal atoms bond to form a solid substance.
How to shell electrons that move throughout the structure
The greater the number of three moving electrons, the greater the active forces in the metal this results in a high melting and boiling point
Properties of metalically bonded things
Electrical conductivity free of electrons can move around and carry the electrical current
All metals are good conductive of heat free over electrons carry energy throughout the metal
Malleability metals are malleable as metal irons can slip past each other without difficulty
Smart materials:
-photochromic pigments
Special materials change the color to specific temperature. Examples include mugs T-shirt, and battery power indicators.
Smart materials:
-polymer gel
Hydrogel are common examples. they can absorb or excel water as well as shrink/swell due to changes in pH uses, include artificial muscles filling for nappies, and in houses threatened by forest fires
Smart materials:
-shape memory polymer
These are plastics that can regain their original shape when heated. when heated they can be stretched or deformed
When it cools, it remains in the molded shape if it shape is altered, it can be returned to its original shape by reheating used in gum, shields, helmets, and window frame ceiling