Unit 1 - Topic 5 - Bonding, Structures, and Properties Flashcards
Describe classification
When substances that have similar properties are grouped together.
How many different types of bonding are there?
3
What are the different types of bonding?
Metallic Bonding:
Only found in metals
Ionic Bonding:
Found in compounds made from metals and non-metals
Covalent Bonding:
Found in substances made only from non-metals.
Found in both elements and compounds.
Which non-metallic elements don’t have covalent bonding and why?
Noble Gases
These elements cannot form bonds and exist as single atoms. They are described as MONATOMIC.
What kind of information can testing for conductivity provide?
Useful information about the type of bonding in a substance.
Whether a substance is a solid, liquid or dissolved in water to form a solution can affect the substance’s conductivity.
Conclude conduction and solids
The only solids which conduct electricity are metals and carbon in the form of graphite.
The solids which conduct electricity all have metallic bonding EXCEPT carbon (graphite) which has covalent bonding.
Conclude conduction and liquids
The only liquid at room temperature which conducted electricity was mercury.
Mercury has metallic bonding.
Apart from mercury, all the liquids at room temperature have covalent bonding.
The only melted solid which conducted was lead(II) bromide.
Lead(II) bromide has ionic bonding.
Conclude conduction and solutions
The only solutions which conducted electricity contained an ionic compound.
When does metallic bonding conduct electricity?
When solid or liquid
When does ionic bonding conduct electricity?
When liquid or in solution
When does covalent bonding conduct electricity?
Never except carbon in the form of graphite
What are ionic compounds made of?
Ions not neutral atoms
What happens during conduction?
The ions move to the electrodes of opposite charge.
When the ions touch the electrodes they get changed back to atoms.
This reaction is called ELECTROLYSIS.
Why do ionic compounds only conduct when molten (liquid) and in solution?
Because their ions are FREE TO MOVE ABOUT. When solid the ions cannot move.
What is electrolysis?
The breakdown of an IONIC COMPOUND using electricity.
The reaction occurs on the electrodes during conduction.
What are the atoms in a metal held together by?
Metallic bonding
Are metals affected by conducting electricity?
No
Describe the structure of metals
The atoms in a metal are packed very close to each other.
This allows the electrons on the outer energy level of each atom to move between the atoms
Describe conduction in metals
During conduction, electrons are pushed in from the negative terminal of a battery or power supply
Electrons move towards the positive terminal.
When a METAL conducts the charged particles which move as the current are ELECTRONS.