1.3 Bonding (AS) Flashcards
Where does ionic bonding occur
non-metal and metal
Describe how ionic bonding works
Electrons transferred from the metal to the non metal, to achieve full outer shells
How is a giant ionic lattice formed through ionic bonding
electrons are transferred, creating charged particles called ions,
oppositely charged ions attract through electrostatic forces of attraction,
forming giant ionic lattices
Give an example of an ionic lattice
Sodium Chloride
State the formulas for:
1) Sulfate ion
2) Hydroxide ion
3) Nitrate ion
4) Carbonate ion
5) Ammonium Ion
- SO4(2-)g
- OH(-)
- NO3(-)
- CO3(2-)
- NH4(+)
Where does covalent bonding occur
Between non-metal and non-metal
How does covalent bonding occur
Electrons are shared betwen the two outer shells in order to achieve a full outer shell of electrons.
What is a dative/ coordinate covalent bond
When both of the electrons in the shared pair are supplied from a single atom
Give an example of a dative bond
NH4(+)
NH3 has a lone pair, forms a dative bond with H+
How does metallic bonding occur
Lattice of positively charged ions, surrounded by a sea of delocalised electrons, forming strong electrostatic force of attraction between oppositely charged particles
How does charge on the positive ion affect the attractive force
Greater charge on positive ions, stronger attraction as more electrons are released into the sea
How does size affect attraction
Larger size, weaker attraction because of greater atomic radius
Name the four main types of
crystal structures
- Ionic
- metallic
- simple molecular
- macromolecular
Explain melting and boiling point in ionic crystal structures
- High Melting / Boiling point
- strong electrostatic forces of attraction
- holding the ionic lattice together
- require alot of energy to overcome
Explain electrical conductivity in ionic substances
- Can conduct in molten / solution
- ions are separated and no longer held in lattice
- free to move carry a flow of charge
- and therefore electrical current
Why are ionic substances brittle
(Hard but liable to break easily)
Layers of alternating charges distorted, like charges repel, breaking the lattice into fragments
Explain conductivity in metallic structures
- Good conductors
- sea of delocalised electrons
- carries charge flow
- allowing current to pass through
Why are metals malleable
- Layers of positive ions can slide over each other
- delocalised electrons prevent fragmentation
What is the only metal that is liquid at room temperature
Mercury
Explain melting points of metallic structures
- High melting points
- strong electrostatic forces between positive ions and delocalised electrons
- require alot of energy to overcome
Describe a simple molecular structure
Consisting of covalently bonded molecules
Held together by weak Van Der Waals forces
Give an example of a simple molecular structure
Iodine
Explain the melting / boiling point of simple mplecular structures
- Low melting / boiling point
- weak van der waals forces
- easy to overcome
Why are simple molecular substances poor conductors
Their structure contains no charged particles to carry charge flow
Describe macromolecular substances
Macromolecular structure is covalently bonded into a giant lattice structure
Give 2 examples of macromolecular substances made from carbon
Diamond and Carbon
Why is diamond one of the strongest materials known
Each of the carbon atoms is bonded to further four carbon attoms
Why can graphite conduct electricity
- Each carbon is bonded to three other carbons in falt sheets
- Free electrons can move between layers
- Conducting electricity
How much distortion does one lone pair of electrons cause
2.5(degrees)
Give Name and bond angle
- 2 bonding pairs
- 0 lone pairs
Linear shape
Bond angle 180°
Give Name and bond angle
- 2 Bonding pairs
- 2 Lone pairs
V - Shaped
Bond angle 104.5°
Give name and bond angle
- 3 Bonding pairs
- 0 Lone pairs
Trigonal Planar
Bond angle 120°
Give name and bond angle
- 3 bonding pairs
- 1 Lone pair
Triangular Pyramid
107°
Give name and bond angle
- 4 Bonding pairs
- 0 Lone pairs
Tetrahedral
109.5°
Give name and bond angle
- 5 Bonding pairs
- 0 Lone pairs
Trigonal Bipyramid
90° and 120°
Give name and bond angle
- 6 Bonding pairs
- 0 Lone pairs
Octahedral
90°
Define electronegativity
The ability of an atom to attractive a pair of electrons with negative charge
Explain how electronegativity changes across a period
- Elecgronegativity increases along a period
- Atomic radius decreases
Explain how electronegativity changes down a group
- Electronegativity decreases down a group
- Shielding increases
When does a polar bond form
When two atoms have different electrongetaivities, and one atom draws electrons closer to itself, and away from the other producing partial charges
Give an example of a polar molecule
- Water
- Hydrogen Fluoride
What can polar molecules with permenant dipoles form
Lattice of molecules
Similar to an ionic lattice
Name the three types of intermolecular forces
- Van Der Waals
- Permenant Dipoles
- Hydrogen Bonding
What does the strength of Van der Waals depend on
Mr of the molecule and its shape
Explain the link between size of molecule and Van der waals
The larger the Mr
Stronger Intermolecular forces
More opportunity for Van der Waals
Where do Hydrogen Bonds form
- Hydrogen and Nitrogen
- Hydrogen and Oxygen
- Hydrogen and Fluorine
(between the most electronegative elements)
How do hydrogen bonds form
The Lone pair on the atom forms a bond with the hydrogen, shown with a dotted line
What are the melting points like with hydrogen bonding
High melting / boilings
strongest intramolecular force
alot of energy to overcome
