Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
What is a metallic bond? |
positive ions in a sea of delocalised elerctrons (between atoms of metal) |
|
|
What is a covalent bond? |
The attraction of the two positive nuclei for the shared pair of negative electrons forms the covalent bond |
|
|
What are ionic bonds? |
The attraction between oppositely charged ions |
|
|
Give some characteristics of metallic bonding? |
~ high melting and boiling points ~ strong, requires alot of energy to break it ~ conducts energy ~ insoluble in most solvents |
|
|
What is the term molecule used to describe? |
a relatively small group of atoms held together by covalent bonds |
|
|
Diatomic meaning? |
a molecule that contains only two atoms |
|
|
tetrahedral? |
when a molecule has 4 bonds |
|
|
trigonal pyramid shape? |
if a molecule has three bonds |
|
|
Angular shape? |
when molecule has two bonds |
|
|
Linear shape? |
molecule has one bond |
|
|
how many types of covalent bonds are they? |
2 |
|
|
what is a simple covalent? |
~ low melting and boilig pointa ~ when these substances change only weak forces of attraction are broken not the strong covalent bonds ~ small amount of energy required
~ |
|
|
What is a covalent network? |
~ high melting and boiling points ~ the strong covalent bonds have to be broken by large quantities of energy - do not disolve - dont conduct electrcity |
|
|
Why dont covalent bonds conduct electricity? |
made up from molecules that are uncharged and dont have free elctrons |
|
|
what is the exception to the rule that covalent substances dont conduct electricity? |
carbon becuase it has delocalised electrons |
|
|
metal electrons ; |
lose electrons to acheive a noble gas arrangement no longer neutral form positive metal ions |
|
|
Non metal electrons; |
gain electrons to achieve a noble gas arrangement no longer neutral form negative non metal ions |
|
|
ionic compounds; |
~high melting and boiling points ~dont conduct electricity as they dont contain free ions ~soluble as the moving ions can carry the charge ~ when disovled conduct electricty as the moving ions can carry the charge~ molten ionic compounds conduct as they have free ions that can move ~ molten ionic compounds conduct as they have free ions that can move |
