Bonding Flashcards
Define ionic bonding
The electrostatic attraction between oppositely charged ions
How are ions held in ionic bonding?
By electrostatic forces of attraction held in fixed positions
What is broken when the ionic compound melts?
Electrostatic forces of attraction
Do ionic compounds have a high or low boiling/melting point and why?
High because low of energy needed to OVERCOME strong EFoA
Do ionic compounds conduct as a solid or liquid?
Not as a solid.
Yes as a liquid because ions (charged particles) can flow
(Electricity being the flow of charged particles)
Define metallic bonding
The electrostatic attraction between the delocalised e- and positive metal ions
How are the ions held in place in a metallic compounds
By EFoA
Describe the structure of metallic compound
Giant lattice of positive metal ions in a “sea” of delocalised e-
What is broken when metallic compounds melt?
EFoA
Metallic compounds:
High or low melting point?
Why?
High melting point because lots of energy needed to OVERCOME strong EFoA
Does a metallic compound conduct as a solid or liquid?
Yes as both because delocalised e- can flow
Are there any other special qualities about metallic compounds?
Hint: yes, yes there are
Malleable and ductile as layers of ions can slide over each other
For ionic and metallic:
When the charge of the ions becomes higher (e.g Na+ vs Al3+) they become…. and the melting points become ….
Stronger
Higher
What is a simple molecular bond?
Negatively charged pair of e- attracted to positively charged nuclei of the atoms involved
How are simple molecular molecules held together?
Small molecules attracted together by weak intermolecular forces
What is broken when a simple molecular melts?
WImF broken when melted
Do simple molecular have a low or high melting point and why?
Low
Only WImF need to be overcome not breaking the strong covalent bonds
Does a simple molecular conduct as a solid or liquid?
No as there are no charges particles
They can flow but not charged
As the simple molecular chain gets longer the melting and boiling points get ……. because there are …. ImF so ………. energy is needed to ………. them
Higher
More
More
Overcome
What is a covalent bond?
The electrostatic attraction between a shared pair of e- and the nuclei of 2 atoms
How do giant covalent bonds work?
Negatively charged pair of e- attracted to positively charged nuclei of atoms involved
Describe the structure of diamond
Each C atom bonded to 4 others STRONGLY in a repeating tetrahedral shape
Do diamonds have high melting points and why?
V. High melting points because v. strong covalent bonds are broken taking a lot of energy’s
Does diamond conduct?
No—no charged particles
Describe the structure of graphite
Each C atom bonded to 3 others with one e- left delocalised. They’re in massive sheets attracted to each other by WImF
High melting point for graphite?
Why?
V. High because so many WImF to break that it takes so much energy that the covalent bonds r broken
Does graphite conduct?
Yes—delocalised e- can flow
Which compounds r water soluble?
Why?
Ionic and a few simple molecular ONLY.
Water is a polar solvent so is attracted to ions and “pulls“ them apart so the ionic compound dissolves
