Structure And Bonding Flashcards
What forms ionic bonds?
Metals and non metals
What forms simple molecular bonds?
Most nonmetals with other nonmetals
3 examples giant covalent structures?
Graphite, diamond and SiO2
What forms metalling bonds?
Metals on their own
Properties of ionic bonds?
- High MP + BP
- Conducts electricity as liquid/solution but not as solid
Properties of simple covalent bonds?
- Low MP + BP
- Does not conduct electricity
Properties of giant covalent structures?
- High MP + BP
- Does not conduct electricity
- Graphite is soft/malleable
Properties of metallic structures?
- High MP + BP
- Conducts electricity
- Malleable
How do ionic bonds form?
Atoms gain or lose electrons to form charged ions with noble gas structures
Why do ionic structures conduct electricity as a liquid/solution but not as a solid?
Because as a solid neither electrons nor ions are free to move about.
When dissolved in water ions are free to move around
What particles carry electric charge?
Electrons or ions
How to simple molecular bonds form?
Atoms share electrons in covalent bonds to get the noble gas electronic structure
Why do simple molecular structure not conduct electricity?
There are no free electrons
Molecules are not charged
What is present between molecules in a simple molecular structure?
A weak inter molecular force
In an ionic bond what attracts the ions together?
Strong electrostatic attraction
What holds atoms together in a giant covalent structure?
Very strong covalent bonds between atoms
How does a giant covalent structure form?
Atoms share electrons in covalent bonds to form a giant covalent lattice
How is graphite an exception of giant covalent structures?
Explain it’s properties
It conducts electricity because it only forms 3 covalent bonds there is an extra electron that is delocalised and can conduct electricity.
It is malleable because there is a weak bonding between layers, allowing them to slide
How do metallic bonds form?
Metal atoms achieve a full outer shell of electrons by losing their outer electrons to a ‘sea’ of delocalised electrons.
Why can metals conduct electricity?
Because delocalised electrons are free to move and carry electricity
How are things in metals held together?
There is a strong electrostatic attraction between the positive ion and the sea of negative electrons
Why is metal soft?
Layers are able to slide over each other
What is an allotrope?
When an element exists in several different forms of the same state.
Practice drawing a diamond and graphite structure
K
What is the loss of electrons called?
What is the gain of electrons called?
Loss of electrons = oxidisation
Gain of electrons = reduction
What’s the relationship between ionic charge and the MP and BP of an ionic compound ?
The higher the charge the higher the MP and BP
Because there is a stronger electrostatic attraction
What is the attraction between the atoms in a simple molecular structure?
An attraction between the positive nuclei and the negative electrons
What is an electrical current?
The flow of charges through a conducting substance
What is the relative mass of a proton, neutron and electron?
Proton - 1
Neutron - 1
Electron - 1/2000
What is the charge of a proton, neutron and electron?
Proton +1
Neutron 0
Electron -1
