Metals Flashcards
What are the two components in the structure of a metal?
A lattice of positive metal ions and a ‘sea’ of delocalised electrons.
Define metallic bonding:
Metallic bonding is the electrostatic attraction between the positive metal ions and the negative delocalised electrons.
Is metallic bonding a usually strong or weak attraction?
Usually a very strong reaction.
What are the 3 properties of metals?
-High melting points
-Conduct electricity
-Malleable
Why do metals have high boiling points?
Because the metallic bonding is usually very strong, so lots of energy is needed to break it.
Why do metals conducts electricity?
Because the delocalised electrons are free to move through the lattice.
Why are metals malleable?
Because the layers of metal ions can slide over each other.
What is thermal decomposition?
When heat energy is used to break down a substance.
What do metal carbonates decompose into?
Metal Carbonate ->
Metal Carbonate -> Metal Oxide + Carbon Dioxide
What does the thermal decomposition of copper carbonate look like?
Copper carbonate (green solid) -> Copper Oxide (black solid) + Carbon Dioxide (colourless gas)
Carbon dioxide is often collected by downward delivery, what does this mean?
As carbon dioxide is denser than air, it sinks to the bottom of a tube and can stay there until you want to use it.
Metal + Water ->
Metal + Water -> Metal Hydroxide + Hydrogen
What are the two observations (in the metal + water reaction) between magnesium and water?
-Effervescence as hydrogen is produced
-Solid disappears due to being used up in the reaction
What is another name for the metals in group 1 of the periodic table?
Alkali metals.
What is one word to describe the reaction between group 1 metals and water?
Violent.
What are the four similar observations in the reactions between Li, K and Na with water?
-Solid floats
-Effervescence
-Solid Moves
-Solid disappears
Why does the solid float in a group 1 metal + water reaction?
It is less dense than water.
Why does the solid move in a group 1 metal + water reaction?
The effervescence propels it around the surface of the water.
Why does the solid disappear in a group 1 metal + water reaction?
It is used up in the reaction.
What colour does a universal indicator turn in water after a group 1 metal and water reaction?
Why?
Dark blue because the metal hydroxides are alkalis because they donate OH-.
What is the reaction between Li and water like?
Fast.
What is the reaction between Na and water like?
Faster than lithium and Na melts
What is the reaction between K and water like?
The fastest, K melts and there is a lilac flame.
What is the group 1 metal reactivity trend?
The group 1 metals get more reactive as you go down the group.
What do group 1 metals have to do to their electrons when they react?
They have to lose 1 electron to get an outer shell
Why do group 1 metals become more reactive as you go down the group?
It’s easier for them to lose an electron when you go down because:
- The atoms get bigger and have more shells
- the outer-electron is further from the nucleus
- The attraction between the nucleus and outer-electron is weaker
- Less energy is needed to break the attraction
Metal + Steam -> ?
Metal + Steam -> Metal oxide + Hydrogen
Describe the reaction between magnesium and steam:
-Usually conducted in a horizontal tube
-Wet wool is heated at the end of the tube to generate steam for the Mg to react with
-The H2 gas is ignited to safely destroy it
Why do metals react with cold water and hot steam to produce different products?
Steam has more energy, so both bonds in the water molecule can break.
Acid + Metal ->
Acid + Metal -> Salt + Hydrogen
A salt is a compound formed when…
A salt is a compound formed when H is displaced from an acid.