bonding, structure and properties of matter Flashcards
what is ionic bonding?
form between metals and non-metals. It involves the transfer of electrons in the outer shells.
what is covalent bonding?
When atoms share pairs of electrons, they form covalent bonds. These are STRONG bonds
Examples of covalently bonded substances with giant covalent structures:
diamond and silicon dioxide.
What are the three types of structure that can be formed by
covalent bonding?
Small molecules, very large molecules, giant covalent molecules.
What are the limitations of using dot and cross diagrams to
represent covalent bonds?
It shows the electrons differently, when they are the same and it does not show the bond angles or shape of the molecule.
The electrons in the outer shell of metal atoms are delocalised and are free to move throughout the structure.
The sharing of delocalised electrons lead to ….
strong metallic bonds.
How are atoms arranged in a metal?
Giant structures of atoms, arranged in a regular pattern,
delocalised electrons.
Why are metallic bonds so strong?
Sharing of delocalised electrons.
What are delocalised electrons?
They are free-moving electrons within structure; not associated with a particular atom.
Why are the particles that make up a metal described as positively charged?
The metal atoms lose outer shell electrons and therefore there are more protons (+) than electrons (−).
solids (s) =
Close together, regular pattern, vibrate on the spot.
liquids (l) =
Close together, random arrangement, move around each other.
gases (g) =
Far apart, random arrangement, move quickly.
aqueous solution (aq) =
water that contains one or more dissolved substance.
solid → liquid =
melting