metals Flashcards
(40 cards)
describe the structure of a metal
- lattice of positive ions
- sea of delocalised electrons
define metallic bonding
the electrostatic attraction between the positive metal ions and the negative delocalised electrons
is metallic bonding a strong or weak attraction
very strong
what is thermal decomposition
a thermal decomposition reaction is when heat energy is used to break down a substance
what do metal carbonates decompose into
metal oxides and carbon dioxide
metal carbonate -> metal oxide + carbon dioxide
what occurs when copper carbonate is thermally decomposed
turns from green to black and releases co2
what is downward delivery
- carbon dioxide is denser than air so its often collected by downward delivery
- this means it sinks to the bottom of the tube
-and it stays there until you need to use it
what are the properties of metals
- high melting and boiling point
- conduct electricity
- malleable
list the metal reactivity series from low to high
- Au (lowest)
- Ag
- Cu
- H
- Pb
- Fe (middle)
- Zn
- C
- Al
- Mg
- Ca
- Li
- Na
- K (highest)
give the metal + water equation
- metals react with cold water to form metal hydroxides and hydrogen
- metal + water -> metal hydroxide + hydrogen
observations of metal + water reactions
- effervescence: due to the hydrogen gas produced
- solod disappears: due to being used up in the reaction
what are the metals in group 1 called and how do they react in water
- alkali metals
- they react violently in water
what are the reactions of Li and K in water
- solid floats: it is less dense than water
- effervescence: hydrogen gas is produced
- solid moves: it is propelled by the effervescence across the surface
- solid disappears: it is used up in the reaction
what is the group 1 reactivity series
Li
na
k
rb
cs
- the group 1 metals get more reactive as you go down the group
why do group 1 metals get more reactive as you go down the group
when a group 1 metal reacts it loses its outer shell electron to get a full outer shell, this happens more easily as you down the group because:
- the atoms get bigger and have more shells
- the outer electron is further from the nucleus
- the attraction between the nucleus and the outer electron is weaker
what is the equation for the metal + steam reactions
metal + steam -> metal oxide + hydrogn
where does the metal+steam reaction take place
horizontal tube
what is the method for reacting magnesium and steam
- mg + h2o -> mgO + H2
- wet wool is heated to generate steam for the mg to react with
- the h2 gas produced is ignited safely to destroy it
why do metals react with cold water and steam to produce different products ?
steam gas more energy so bith bonds in the water molecule can break
what is the acid + metal equation
acid + metal -> salt + hydrogen
what are the observations of an acid + metal reaction
- effervescence: because hydrogen gas is produced
- the metal disappears: because its used up in the reaction
what is a displacement reaction
more reactive metals can displace less reactive metals from their compounds
observations of a displacement reaction
- solid colour change
- solution colour change
what is an ore
metals found in the earths crust as compounds of oxygen and sulphur. this is because over a long time those metals have reacted with oxygen and sulphur.
