U1 Chemical Changes and Structure Flashcards
What is a covalent bond?
Bond between two non-metals by their shared attraction for a pair of electron
What are the 7 diatomic elements?
Iodine
Bromine
Oxygen
Hydrogen
Chlorine
Fluorine
Nitrogen
What are the two types of covalent bonds?
Covalent Molecular and Covalent Network
Properties of a Covalent Molecular substance
Low Melting and Boiling Points
Strong Covalent bonds between molecules
Weak intermolecular forces
Do not conduct as they have no free ions
Properties of a Covalent Network
Network of strong covalent bonds
Very high boiling and melting points
Do not conduct
Do not dissolve
What happens to the molecules when a substance changes state?
The intermolecular forces weaken
How are ions formed?
When an atom gains or loses electrons to gain a full outer electron shell
How do ionic bonds form?
Through the electrostatic connection of positive and negative ions
What is an ionic compound made of?
Metal and Non-Metal
What is the structure of an ionic compound?
Ionic Lattice
Properties of an ionic compound
High melting and boiling points
Soluble in water
Conducts in molten or as a solute
Why do ionic compounds conduct as a solution or molten?
The lattice structure breaks allowing ions free movement
