C2: Bonding, Structure, and Properties of Matter Flashcards
What is an ion?
A charged particle
When are ions made?
When electrons are transferred
Why do atoms form ions?
To try and gain or lose more electrons to get a full outer shell.
What ions do metals form?
Positive ions
What ions do non metals make?
Negative ions
What groups are most likely to form ions?
1, 2, 6 and 7
What are the 3 types of bonding?
Ionic, metallic, covalent
What is an ionic compound?
The transfer of electrons
How does ionic bonding work?
The oppositely charged ions are strongly attracted to each other by electrostatic forces as opposites attract.
What structure do ionic compounds have?
Regular lattice
How is the giant ionic lattice shape held together?
The electrostatic forces of attraction between the oppositely charged particles, in all directions of the lattice.
What is an example of a giant ionic lattice and what ion sit is made of?
Sodium chloride (table salt) is made of Na+ and Cl- ions
What are the properties of an ionic compound?
- high melting and boiling points due to the many strong ionic bonds(electrostatic)
- don’t conduct electricity in solids but in liquids the ions are free to more so then can carry the charge
What is covalent bonding?
The sharing of electrons
What elements have covalent bonds?
Non metals
Are covalent bonds strong and why?
They are strong as the positively charged nucleus are attracted to the negatively charged shared pair of electrons by electrostatic forces.
How do covalent bonds work?
Both atoms share one electron with the other.
How many covalent bonds does element have?
Enough to get a full outer shell
What is a simple molecular substance?
A substance made up of molecules containing few atoms joined together by covalent bonds
What are some properties of simple molecular substances?
- very strong covalent bonds but very weak forces of attraction
- low melting and boiling points as you need to break the intermolecular forces not the covalent bond
- don’t conduct electricity as they arn’t charged
What is polymer?
A long chain of repeating units
How are the atoms joined in polymers?
Covalent bonds
Why are most polymers solid at room temperature?
The intermolecular forces are greater so it takes more energy to over them.
How are the boiling points on ionic or giant molecular compounds different?
The intermolecular forces are weaker than ionic and giant molecular compound so they have lower boiling points
What structures do giant covalent structure have?
Macromolecules
How are the atoms bonded in giant covalent structures?
Strong covalent bonds
What are the melting points like in giant covalent structures?
Very high as they have many strong covalent bonds that need a lot of energy to be broken.
What are the main examples of giant covalent structures?
Diamond, Graphite and silicon dioxide
What atoms are diamond and graphite made up of?
Carbon
What atoms are silicon dioxide made out of?
Silicon and oxygen
How is diamond structured?
Each carbon atom bonds to form 3 covalent bonds in a very rigid giant covalent structure
How is graphite structured?
Each carbon atoms forms 3 covalent bonds to create layers of hexagons. Each carbon atoms also has a delocalised electron.
What are the properties of diamond?
. very hard as of the covalent bonds
. very high boiling and melting point
. doesn’t conduct electricity
What are the properties of graphite?
. slide over each other a s the layers are held weakly together
. high melting point
. conducts electricity
What can graphite be used for?
Lubricating matter
What is graphene?
One layer of graphite
What are the properties of graphene?
. strong because of the covalent bonds
. conducts electricity
What can graphene be used for?
To strengthen materials without adding much weight as it is only one atom thick.
What is a fullerene?
A molecule of carbon that is shaped like a closed tube or hollow balls.
What are fullerenes used for?
Caging other molecules
What is an example of fullerene being used?
Delivering a drug to the body, lubricating matter, catalysts
What do many fullerenes form?
Nanotubes
What is a nanotube?
Tiny carbon cylinders
What are the properties of a nanotube?
. conduct electricity and heat
. don’t break when stretched
. very strong
What is metallic bonding?
The bonds between metals
How does metallic bonding work?
The metals have delocalised electrons which causes strong electrostatic forces between the positive nucleus and the electrons
Are metallic bond weak?
No they are very strong due to the strong electrostatic forces
What produces the properties in a metallic bond?
The delocalized electrons
What are metals boiling and temperatures like?
Very high
Are metals good conductors of heat and why?
Yes because the delocalised electrons can carry charge
Why are metals mixed with other metals?
It makes them harder
Why are alloys stronger than pure metals?
Different elements have different sized atoms so they distaught the shape of the pure metal making it harder fir them to slide over each other.
What does an object state of matter depend on?
. material
. temperature
. pressure
Why are gases free to move?
Very weak forces of attraction
What is a negative of the particle theory model?
It doesn’t show the forces so you don’t know how strong they are
Explain how substances change state when heat is added?
- the particles gain more energy
- the particles vibrate more which weakens the forces
- at melting point the particles have enough energy to break free so a solid turns into a liquid
- the liquid is still heated so the particles gain even more energy
- this energy makes the particles move faster which weakens and breaks the bond that holds the liquid together
- the particles now break their bonds and becomes a gas this is called evaporation
What happens to the state of a substance when it is cooled?
- as a gas cools, the particles no longer has energy to overcome the forces of attraction
- bonds form between the particles
- many bonds have now been formed so it starts to condense
- the liquid cools so the particles more even less
- more bonds are made
- the particles are now held in place by these bonds are change into a solid this process is called freezing
What are the types of nanoparticles?
Coarse particles, fine particles, nanoparticles
What are coarse particles?
Dust
How big are coarse particles?
2500nm to 10,000nm
How big are fine particles?
100nm to 2500nm
How big are nanoparticles?
1nm to 100nm
How do you work out the surface area to volume ratio?
surface area/ volume
What are the uses of nanoparticles?
Nanomedicine, catalysts, electric circuits, cosmetics
What some disadvantages of nanoparticles?
We don’t know the side effects of nanoparticles on health when used in medicine, they may damage the environment when washed away
