|What is a compound?
|A substance in which two atoms of two or more elements are chemically combined.
|What does chemical bonding involve?
|Either transferring or sharing electrons in the highest occupied energy levels (shells).
|What does chemical bonding achieve?
|The electronic structure of a noble gas
|When atoms form chemical bonds, what do they form?
|What happens when an atom looses an electron?
|It becomes positively charged.
|What happens when an atom gains an electron?
|It becomes negatively charged
|What to metal atoms form?
|What do non-metal ions form?
|What is an ionic bond?
|The strong electrostatic forces of attraction between oppositely charged ions.
|How would you work out how many charges an ion should have?
|- When it's a metal ion the charge is equal to the group number of the metal. - When it's a non-metal the charge is equal to the group number minus 8.
|Draw a lithium atom becoming positive. (Li 2,1)
Image: diag_lithium.gif (image/gif)
|Draw a fluorine atom becoming negative. (F 2,7)
|What is an ionic compound?
|When metals and non-metals share electrons forming ions. A giant structure of ions.
|What are the group one elements called and what do they form when reacting with non-metals?
|Alkali metals. They form an ionic compound with a single positive charge.
|What are the elements in group 7 called and what do they form when they react with metals?
|Hallogens. They form ionic compounds with a single negative charge.
|When atoms share pairs of electrons, what do they form?
|What do metals consist of in structure and bonding?
|Giant structures of atoms arranged in a regular pattern.
|What happen to the electrons in the highest occupied energy levels (shells) of metal atoms?
|They are delocalised and so move freely through the whole structure. This corresponds to a structure of positive ions with electrons between ions holding them together by strong electrostatic connections.