Topic 2- Structure and Bonding Flashcards
Ionic, metallic, covalent bonding (22 cards)
Definition of ionic bonding
Bonding of a metal and non metal to gain a full outer shell
Cation
Positive ion- an atom that loses electrons
Anion
Negative ion- an atom that gains electrons
Metals lose/gain electrons?
Lose to become positive
Non-metals lose/gain electrons?
Gain to become negative
Rules for ionic bonding drawing
- Draw the elements, only draw the valence electrons, metal and non-metal electrons MUST look different
- Draw the ions, there should be no electrons on the metal ion
- Ionic bond, put square brackets around both ions, put the charge of the ion outside the bracket
Metal ion charge
Same as the group number
Non-metal ion charge
8-group number
What holds the ions together in ionic bonding
A strong electrostatic force of attraction called an ionic bond between the positive and negative ions
Definition of metallic bonding
Each metal loses its valence electrons, these freely move in the lattice between the now positively charged metal ions (between a metal and a metal)
Ionic bonding properties
Directional therefore brittle, strong electrostatic force between positive and negative ions
Directional
Force of attraction goes up and down
Non directional
Force of attraction acts in all directions
Metallic bonding properties
Strong electrostatic force between slightly positive metals and a sea of delocalised (free moving) valence electrons, non directional therefore malleable
Definition of covalent bonding
When two or more non metals combine they share electrons
Giant covalent networks
Diamond, Graphite, Silicon Oxide (sand)
Ionic compound formula swap and drop
- Swap the charges
- Drop the number
- Cancel any like charges
The covalent bond between non metal atoms is very strong, forming individual covalent molecules however
The attractive force between individual molecules is very weak
Allotrope
Two different forms of the same element eg. diamond and graphite are both made from carbon atoms
Electrical conductivity
For something to conduct electricity there must be free moving charged particles
Charged particles can be
Electrons or ions
Solubility
If a solid or liquid can dissolve in a solvent it is soluble, if something is soluble, it is because the solvent is attracted to the solute and that attractive force can overcome the bond/ force between the solute