Bonding Flashcards
Describe the structure of a giant ionic lattice
Ionic compounds form giant ionic lattices, a regular crystal structure held together by ionic bonds. Ions of opposite charges are placed adjacent to one another due to attraction via electrostatic force.
Describe the melting/boiling point of ionic compounds
Ionic compounds have high melting and boiling points. This is because the electrostatic forces between molecules of opposite charge in a giant ionic lattice are very strong and require lots of energy to overcome
Describe the electrical conductivity of ionic compounds
Ionic substances can conduct electricity when molten or dissolved. When in a solid states, ions are held in fixed positions within a giant ionic lattice. When in a liquid or aqueous state, they are free to move and carry an electrical current.
Why are ionic compounds often brittle?
When a giant ionic lattice is distorted the layers of alternating charge slide, causing contact between ions of same charge. This causes the ions to repel and break apart into fragments
Describe the structure of simple molecular compounds
Simple molecular compounds are arranged in a regular lattice and held together by Van der Waals forces
Describe the melting/boiling point of simple molecular substances
Simple molecular substances have low melting and boiling points, as they are held together by weak Van der Waals forces that require little energy to break.
Describe the electrical conductivity of simple molecular substances
Simple molecular substances are very poor electrical conductors as their structure do not contain any charge particles or delocalised electrons
Describe the structure of a giant covalent lattice
Giant covalent lattices consist of a large number of atoms that are joined by multiple covalent bonds, forming a giant lattice structure.
Describe the melting/boiling point of giant covalent structures
Giant covalent structures have very high melting points as atoms are held together by multiple covalent bonds. These bonds are very strong, and require a lot of energy to break
Describe the electrical conductivity of giant covalent structures
Giant covalent structures often cannot conduct electricity as they posses no charged particles. Only those with delocalised electrons, such as graphite, can conduct electricity.
Describe the structure of metallic substances.
Metallic substances consist of a lattice of positively charged metal ions that are surrounded by a sea of electrons, and is held together by electrostatic forces of attraction between oppositely charged particles.
Describe the melting/boiling point of metallic substances
Metallic substances have high melting points, as the electrostatic forces of attraction between positive ions and delocalised electrons is very strong, requiring a lot of energy to overcome.
Describe the electrical conductivity of metallic substances
Metallic substances are very electrically conductive. This is because the sea of delocalised electrons in metallic structures are free to move and carry current throughout the lattice.
Why are metallic substances malleable?
Metallic substances are malleable as layers of positive ions are able to slide over one another when distorted. The delocalised electron can move around to lattice to prevent fragmentation.
Define electronegativity
Electronegativity is “the power of an atom to attract negative charge towards itself within a covalent bond”
