Bonding and Physical Properties
This final page summarizes the relationship between bonding and physical properties for AQA A Level Chemistry, tying together concepts from ionic, covalent, and metallic bonding.
The page presents a comparative overview of different types of structures and their properties:
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Ionic compounds:
High melting and boiling points
Brittle when solid
Conduct electricity when molten or dissolved
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Simple molecular structures:
Low melting and boiling points
Soft or gaseous at room temperature
Poor electrical conductors
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Giant covalent structures:
Very high melting and boiling points
Hard and strong
Variable electrical conductivity e.g.,diamondvs.graphite
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Metallic structures:
Variable melting and boiling points
Malleable and ductile
Good electrical conductors
Highlight: Understanding the relationship between bonding type, structure, and physical properties is crucial for predicting and explaining the behavior of different substances.
The page emphasizes the importance of considering both the type of bonding within a substance and the forces between particles when explaining physical properties.
Example: The high melting point of sodium chloride NaCl can be explained by the strong ionic bonds in its giant ionic lattice, while the low melting point of iodine I2 is due to weak van der Waals forces between simple molecules.
The concept of structure-property relationships is reinforced, encouraging students to apply their knowledge of bonding to explain and predict the properties of various substances.
Vocabulary: Structure-property relationships refer to the way in which the microscopic structure and bonding of a substance determine its macroscopic physical and chemical properties.