Metallic bonding Flashcards
What are properties of all metals?
Shiny, malleable, ductile, and conduct electricity.
Why can metals conduct electricity?
Because they have delocalised electrons that can carry charge.
What does the electron sea model state?
That a metal is made up of a lattice of positively charged ions, sorrounded by a sea of delocalised electrons.
What is the overall charge in a metal?
0, because the electrostatic attraction between the ions, and delocalised electrons, cancel each other out.
What holds a metalic lattice together?
Electrostatic attraction between positively charged ions, and delocalised eletrons.
Why are metals malleable?
Because positively charged ions, can slide over each other, without breaking the metallic bond.
Define metallic bonding.
Metallic bonding is the attraction between the positively charged ions, and the the negatively charged electrons.
Describe what happens when you melt a metal, and discuss which properties of all metals remain, and which properties of all metals dissapear.
Melting a metal, breaks the regular repeating lattice structure down, and the positively charged ions, are able to flow over each other.
Malleability and ductility, are now lost.
It still conducts electricity, because there are still negatively charged, delocalised electrons, that sill form metallic bonding.
The metal is still shiny.
What happens when you boil a metal?
Boiling a metal, separates it into individual atoms.
All the metal properties are now gone.
It cannot conduct electricity, because all the delocalised electrons from before, are localised electrons, to only one specific metal atom.
There is NO more metallic bonding.
Why do metals have high melting and boiling points?
Because it requires alot of energy, to break the electrostatic attraction between the positively charged ions, and negatively charged, delocalised electrons.
Why do melting points and boiling points of metals, increase across a period?
Overall, the strength of metallic bonding, increases across a period.
This is because, across a period, the ions in the lattice become more highly charged, and the number of delocalised electrons per ion, also increases, thus, increasing the strength of the electrostatric attraction, which means more energy required to break the electrostatic force.
Why do melting points, and boiling points, decrease down a group?
Overall, the strength of metallic bonding, decreases as we go down a group.
this is because down a group, the size of positively charged ions, increases. A larger size, means a longer distance between positively charged ions, and delocalised electrons, thus, decreasing the strength of the electrostatic attraction, which means less energy required to break the electrostatic bond.
What is an alloy?
A metal made out of **TWO **or more elements.
What is a pure metal?
A metal made out of only ONE element.
