Chapter 3 : Bonding 1 + 2

state 3 properties of particle model

1) there are no forces between the particles

2) all particles in a substance are spherical

3) the spheres are solid

What is an ion?

atom that has lost or gained electrons

Which kinds of elements form ionic bonds?

metal and non-metal

Can ionic bond conduct electricity as a solid?

No because ions are in fixed positions. This mean ions cannot move to carry a charge

Can ionic bond conduct electricity when melted or dissolved water?

Yes because ions are free to move and carry a charge

Ionic bonding has high or low boiling/melting points?

It has high boiling/melting points because it has strong electrostatic fore of attraction between the oppositely charged which takes a lot of energy to overcome.

What is covalent bonding?

atoms share or transfer electrons to form strong chemical bonds

Which kinds of elements form covalent bonds?

non-metal and non-metal

Describe bonding of a giant covalent substance

billions of atoms bonded together by strong covalent

What is the example of a giant covalent substance

diamond

Has a giant covalent bond high or low boiling/melting points?

it has high boiling/melting points because it has strong covalent bonds which takes a lot of energy to overcome

What state is a giant covalent bonds at room temperature?

solid

Can a giant covalent bonds conduct electricity?

It is poor to conduct electricity because it bonded to 3 other carbon atoms. This means it has no enough space for delocalised electron to move and carry a charge.

What is simple covalent?

different molecules are held together by weak intermolecular forces

Has a simple covalent high or low boiling/melting points?

it has low boiling/melting points because it has weak intermolecular forces between molecules which takes a little energy to overcome

Can a simple covalent bonding conduct electricity?

No because it doesn’t has delocalised electrons

What state is a simple covalent bonding be at room temperature?

gas or liquid

What are large molecules?

many repeating units joined by covalent bonds to form a chain

What are separate chains held by?

separate chains are held by intermolecular forces that are stronger than in small molecules

What are polymers?

polymers are long-chain molecules formed by joining many molecules(monomers) together

Have large molecules high or low boiling/melting when compared to a small molecules and a giant covalent substances?

they have low boiling/melting points compared to giant covalent substances but higher than for small molecules

Do large molecules have strong or weak intermolecular forces when compared to the small molecules?

they have stronger intermolecular forces than the small molecules which take more energy to overcome

What state are large molecules at room temperature?

solid

Can large molecules conduct electricity?

they cannot conduct electricity because they have no delocalised electrons

the forces that graphite has between the layers is it strong or weak?

it has weak forces between the layers

Why graphite is soft?

layers are not bonded so they can slide over each other

Can graphite conduct electricity?

it can conduct electricity because it has space from unpaired bond because it bonded with 3 other carbon atoms delocalised electrons can use this space to move and carry a charge

What is a graphene?

a single layer of graphite

Does graphene has strong or weak covalent bonds?

it has strong covalent bonds

Can graphene conduct electricity?

Yes

Give two properties of graphene

1) strong

2) can conduct electricity

What graphene can be rolled up to?

it can be rolled up to nanotubes

What are fullerenes?

hollow cage of atoms arranged as a sphere or a tube

Give 3 uses of fullerenes

1) lubricants

2) drug delivery(sphere)

3) high-tech electronics

How many carbon atoms do buckyballs have?

60 carbon atoms(C60)

How do buckyballs can be used?

they can be used to improve acne creams

What is nanotubes?

hollow cylinder of carbon atoms

Give 2 properties of nanotubes

1) high tensile strength

2) can conduct electricity

How nanotubes can be used?

they can be used in sports equipment to increase strength

What kind of atoms that bond in metallic bonds?

metal and metal

What are metallic bonds

the atoms that make up metals form layers

Have metallic bonds high or low boiling/melting points?

they have high melting/boiling points because they have strong electrostatic forces between metal ions and delocalised electrons which take a lot of energy to overcome

Can metallic bonds conduct electricity?

they can conduct electricity because delocalised are free to move through the whole structure

Why can pure metals malleable?

the layers can slide over each other

State properties of pure metal

1) can malleable

2) good conductors of electricity

3) good conductors of thermal energy

4) high boiling/melting points

Give the structure of pure metals

the layers of positive metal ions surrounded by delocalised electrons

Give the bonding of pure metals

strong electrostatic forces of attraction between metal ions and delocalised electrons

What are alloys?

mixture of a metal with atoms of another element

What are nanoparticles?

small particles in comparison to regular sized particles

What are size of nanoparticles

1-100 nm

What are nanoparticles used for? (4)

1) healthcare

2) electronics

3) catalysts

4) cosmetic

How to calculate size of nanoparticles?

diameter of nanotubes divided by diameter of atom