Periodicity Flashcards
What are the four categories that elements can be?
- metallic
- covalent network
- covalent molecular
- monatomic
what is structure of an element?
how particles are arranged
what is the bonding of an element?
how particles are held together
Give examples on the structure of elements
- molecular
- network
- lattice
Give examples on the bonding of elements
- covalent
- metallic
what is metallic bonding?
metallic bonding is the attraction between positive ions and a sea of delocalised electrons.
what is the strength of metals?
80 to 600 kJmol^-1
Give examples of covalent networks (first 20 elements)
boron, carbon, silicon
give examples of covalent molecular (first 20 elements)
hydrogen, carbon, nitrogen, oxygen, fluorine, phosphorus, sulfur , chlorine
give examples of metals (first 20 elements)
lithium, beryllium, sodium, magnesium, aluminium, potassium, calcium
what does a metallic structure consist of?
a metallic structure consists of a giant lattice of positively charged ions and delocalised outer electrons.
give examples of the properties of metals
- malleable (can be drawn into a sheet)
- ductile (can be drawn into a wire)
- conductors of heat
- conductors of electricity
- shiny
How are atoms in a covalent bond held together?
Held together by the electrostatic forces of attraction between positively charged nuclei and negatively charged shared electrons
What is the strength of a covalent bond?
100 to 500 kJmol^-1
name the diatomic molecules
hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine
what are the discrete molecules?
Phosphorus (P4)
Sulfur (S8)
Carbon (C60) Fullerene
what does intermolecular bonding mean?
intermolecular bonding is bonds between molecules
what does intramolecular bonding mean?
intramolecular bonding is bonds within a molecule
what is the strength of London dispersion forces?
1 to 20 kJmol^-1
What does a covalent molecular structure consist of?
discrete molecules held together by weak intermolecular forces.
What are the properties of discrete covalent molecules?
- Low melting and boiling points
- Soft solids
- Brittle
- Do not conduct electricity
What does a covalent network structure consist of?
A giant network of covalently bonded atoms