Flashcards in Unit 2-Bonding,structure and properties of matter Deck (34):
Ions are made when?
Electrons are transferred.
What are ions?
Charged particles that can be single atoms or groups of atoms.
Why do atoms lose or gain electrons ?
To get a full outer shell so they can be stable.
What happens when metals form ions?
They lose electrons from their outer shell to form positive ions.
What happens when non-metals form ions?
They gain electrons into their outer shell to form negative ions.
What are positive ions called?
What are negative ions called?
What is an ionic bond?
When oppositely charged ions are strongly attracted to each other by electrostatic forces.
For an ionic compound what diagram would you draw?
A dot and cross diagram.
What are two disadvantages to dot and cross diagrams?
They don’t show the structure or size of the ions ,or how they’re arranged.
What do ionic compounds have?
A regular lattice structure.
What is a regular lattice arrangement like?
It has electrostatic forces of attraction between oppositely charged ions,in all directions.
What are ionic compounds like?
-They have high melting and boiling points.
-When they are solid the compounds can’t conduct electricity.
-Ionic compounds dissolve easily in water.
What is a covalent bond?
When a non metals react together and so they share pairs of electrons.
As molecules get bigger what happens to the strength of the intermolecular forces?
Do molecular compounds conduct electricity?
All of the atoms in a polymer are joined by what?
Strong covalent bonds.
Do giant covalent structure conduct electricity?
What is diamond made from?
A giant covalent structure.
Why does diamond have a high melting point?
Because it takes a lot of energy to break the covalent bonds.
Does diamond conduct electricity ?
What is graphene?
A sheet of carbon atoms joined together in hexagons.
What does the covalent bonds in graphene mean?
-It makes it strong.
-It makes it really light.
What are fullerenes?
Molecules of carbon shaped like closed tubes or hollow balls that are mainly made up of carbon atoms arranged into hexagons.
Why are fullerenes good catalysts?
They have a large surface area.
What is metallic bonding?
When electrons in the outer shell of a metal is delocalised there are strong levels of attraction between positive metal ions and negative electrons.
Why are metals good conductors of electricity and heat?
They have delocalised electrons.
What are the three states of matter?
What determines something’s state?
Why are nanoparticles useful?
They have a huge surface area to volume ratio.
What can nanoparticles be used for?
-To make new catalysts.
-They can make sterile wound dressings.
Why could nanoparticles be bad for your health?
They could get in to your body and damage cells.
Why could nanoparticles be bad for the environment?
When they are washed away they might damage it.