Metals Flashcards
What two components are there of a metal structure?
a lattice of positive metal ions
a ‘sea’ of delocalised electrons
what is metallic bonding?
The electrostatic attraction between the positive metal ions and the negative delocalised electrons.
Metals are malleable because…
the layers of metal ions can slide over each other
What is thermal decomposition?
This is when a substance breaks down into simpler substances when heated.
metal carbonate -heat->
metal oxide + carbon dioxide
uses of carbon dioxide
fire extinguisher
carbonated drinks
decaffeination
theatre dry ice
metal + water —>
metal hydroxide + hydrogen
group 1 metal properties
stored ‘under oil’ to prevent reaction with oxygen
they are soft and can be cut with a knife
name for group 1
alkali metals
what is the trend in melting points in group 1?
They have low melting points that decrease down the group
When Group 1 metals react, what happens to the Group 1 metal atoms in
terms of electrons?
They lose their outer electron which is transferred to the other element
When a metal reacts it loses its outer electron. Going down the group, this can happen more easily
This is because…
The atoms get bigger and have more shells
the outer electron is further from the nucleus
the attraction between outer electrons and the nucleus is weaker
so less energy is needed to remove the outer electron and so the metal reacts more easily
lithium reaction with water
metal floats on surface of water and fizzes around, then solid disappears
sodium reaction with water
metal melts into a ball, fizzes, may catch fire
potassium reaction with water
lilac flame produced