2. Bonding Flashcards
How are ionic compounds formed?
Transfer of electrons from metal atoms to non metal atoms
Define an ion
Atoms which have lost or gained electrons to gain an overall charge
How do metals form ions
Lose electrons to become positively charged
How do non-metals form ions
Gain electrons to become negatively charged
Define a cation
Positive ions
Define an anion
Negative ions
Define an ionic bond
The electrostatic attractive between oppositely charged ions
Why do atoms lose/gain electrons?
To get a noble gas configuration
Define ionic lattice
The structure where ions are held in a 3D framework
Define lattice
Regular repeated 3D arrangement of ions, atoms or molecules in a solid
What causes the crystalline nature of ionic compounds?
The regular pattern of the ions
Define decrepitation
The cracking noise that ionic compounds make when they’re heated caused by the crystalline structure
Why do ionic compounds have high melting/boiling points?
Because lots of energy is required to overcome the strong electrostatic forces of attraction between oppositely charged ions
What factors affect the strength of the ionic bond?
The size of the ion and the size of the charge
Why are +ve generally smaller?
Bc they’ve lost ions so fewer shells and increased effective nuclear charge so shells drawn in closer
Why are -ve ions generally larger?
Gain electrons so more repulsion of electrons pushes them further apart
Smaller effective nuclear charge bc more electrons with same no of protons
Are ionic compounds soluble?
Most of the time, depending on the strength of the ionic bonds
Why can ionic compounds only conduct electricity in the molten/aqueous state?
Because the ions are free to move and carry charge in these states
Define a covalent bond
One or more shared pairs of electrons between two non-metal atoms
Define a single covalent bond
One shared pair of electrons
Define a double covalent bond
Two pairs of shared electrons
Define a triple covalent bond
Three pairs of shared electrons
What is a bonding pair of electrons?
Pair of electrons that are shared between two atoms
What is a lone pair of electrons?
An unshared pair of electrons that are not involved in bonding
Define a coordinate bond
A bond which has a shared pair of electrons where both electrons are supplied by one atoms