C3 Flashcards
What are the three states of matter ?
Solid , liquid and gas
What are the particles like in a solid ?
Particles in a solid are closely packed together and vibrate around in fixed positions .
What are the particles like in a liquid ?
They are also close together but are free to move , and so can slip and slide over each other
What are particles in a gas like ?
On average they have a lot of space to move around randomly .
How is an ionic bond formed ?
When metals react with non-metals
What ion does a metal form when reacting with a non - metal ?
Positive
What ion does a non-metal form when reacting with a metal ?
Negative ions
The ions that are formed in an ionic bonding are very strong because …
their is an attraction between the positively and negatively charged ions
What is a giant ionic structure or lattice ?
Ionic bonds arranged together a lot .
What is an intermolecular force ?
Forces between separate molecules that hold the substance together .
What is an electrostatic force ?
The force between a negative and a positive charge
In Giant ionic structures what are electrostatic forces like ?
Because their are lots of ionic bonds in a giant structure , it is very strong and the ions are held very tightly .
Does it take a lot of energy to break up a giant ionic lattice ?
Yes
Do giant ionic lattices have high melting and boiling points ?
Yes
What happens when you have supplied enough energy to seperate the ions in a lattice ?
The ions are mobile
What happens when an ion is mobile ?
The ionic solid melts and becomes a liquid.
Can a solid ionic compound conduct electricity ? Why ?
No , because its particles are held in fixed positions.
How can you seperate ions ?
Putting them in a solution or turning them into a molten compound
What happens when non-metals react together ?
Their atoms share pairs of electrons to form molecules .
Are covalent bonds strong ?
Yes
How can you represent the bonding in a covalent molecule ?
. The outer shells
. Dot and cross diagram
. The number of bonds
What are the intermolecular forces like in a covalent bond ?
Weak
Do larger molecules have higher boiling and melting points ?
Yes
Why do covalent bonds have low melting and boiling points ?
Because they have weak intermolecular forces
Do simple molecules conduct electricity ?
No
What is a polymer ?
A substance consisting of very large molecules made by polymerising a large number of repeating units or monomers .
What are three examples of giant covalent structures ?
Graphite , diamond and silicon dioxide
What is diamond ?
It is a form of the element carbon and it is the natural hardest substance in the world
How can artificial diamonds be made ?
By heating pure carbon to very high temperatures under enormous pressures .
What are three properties of giant covalent structures ?
. They have high melting and boiling points
. They are insoluble in water
. Apart from graphite , they are hard and do not conduct electricity
In diamond how many atoms of carbon are connected to one atom of carbon ?
4
In graphite , each carbon atom is connected to how many other carbon atoms ?
Three
What shape do the covalent bonds in graphite form ?
Hexagons
Can the layers in graphite slide over each other ?
Yes
Is graphite a soft material ?
Yes
S
How many electrons do carbon atoms have on their outer shell ?
4
Because carbon atoms have one spare outer electron in graphite what do they do and what are they called ?
They are mobile electrons that can move freely along the layers of carbon atoms , these are delocalised electrons .
How can graphite conduct electricity ?
Delocalised electrons
In other structures the carbon atoms join together to form what …
Hollow cages
Who discovered long shaped molecules of carbon ?
In 1985 , radio astronomers revealed that long chains of carbon exist . The molecule was made up of 60 carbon atoms .
What was the name of the hollow shapes molecules of carbon ?
Buckministerfullerenes or fullerenes
What are cylindrical fullerenes also known as ?
Carbon nanotubes
What properties do carbon nanotubes have ?
High tensile strength and high electrical conductivity
What can fullerenes be used for ?
Drug delivery into the body or radioactive atoms to treat cancer
If you could seperate a single sheet of carbon atoms from graphite you would get a layer of hexagonal rings of carbon atoms called ?
Graphene
What are two qualities of graphene ?
It is an excellent conductor of electricity and is the most reactive form of carbon .
Are layers of atoms in a pure metal able to slide over each other ?
Yes
Why can metals be hammered and bent into different shapes ?
Because their layers of atoms can slide easily over each other
What is an example of a pure metal that is held in a giant metallic structure ?
Iron
What is alloy ?
A Mixture of metals
What are the positive ions in a metallic giant structure bonded to ?
A sea of delocalised electrons
What are three qualities of a metal ?
. Metals are malleable
. They have high melting points
. They are good conductors of heat and electricity
What is metallic bonding ?
Two metals bonded together
Does metallic structure have a strong force of electrostatic attraction ?
Yes
