Ionic/Covalent bonding Flashcards
Ionic is between…
Non-metal and metal!
Covalent is between…
Non-metals.
How to draw ionic.
Brackets around each
Add the charge
Must have full outer shell
How to draw covalent.
Dot/Cross. Must have overlap.
Def. of covalent bond =
Shared pair of electrons
Def. of ionic bond=
Strong forces of attraction between oppositely charged ions.
Why do ionic bonds have high M.P?
Strong forces of attraction between oppositely charged ions which requires a lot of E to break.
Why are ionic bonds brittle?
When a force is applied ions with the same charge end up next to each other and repel causing the bonds to break.
Why can ionic compounds conduct when molten or in solution?
Ions are free to move (carry the current) unlike when its a solid.
Why are alloys stronger than pure metals?
Ions are different sizes T/F the layers can’t slide over each other so EZ.
Name 3 giant covalent structures.
Diamond
Graphite
Silicon Dioxide.
Why does diamond have such a high melting point?
It has a giant tetrahedral structure T/F
Why does graphite have a high melting point?
It has a giant tetrahedral T/F each carbon is bonded to 3 others T/F lots of E to break.
Why can graphite conduct electricity but diamond doesn’t?
In graphite they are bonded to 3 electrons T/F one free carbon atom free to move.
Why can graphite be used as a lubricant?
The carbon atoms are arranged in layers
They slip slide over each other bc weak intermolecular forces. Not much E required to break!
