Extracting Metals And Equilibria Flashcards
What do you observe during the displacement of copper by magnesium?
- The colour of the solution will fade as blue copper sulfate is replaced by colourless magnesium sulfate
- An orange/brown coating of copper forming on the surface of the magnesium
- An increase in temperature as it is exothermic
What is phytoextraction?
- Metal compounds absorbed by roots
- Plant concentrates metal compounds in its shoots and leaves
- Plants burned
- Ash contains metal compounds
What is bioleaching?
- Some bacteria break down low grade ores
- They produce acidic solutions called leachates which contain metal ions
- Produces toxic substances which damage the environment
What is the Haber process?
- Nitrogen (extracted from the air) and hydrogen (obtained from natural gas) are pumped through pipes
- A compressor increases the gas pressure to 200 atmospheres
- The pressurised gases are heated to 450°C and passed through a reaction chamber containing an iron catalyst
- The reaction mixture is cooled so the ammonium liquefies and can be removed
- Unreacted nitrogen and hydrogen are recycled
If the temperature is increased what is the effect and the rate of reaching equilibrium?
- Moves in the direction of the endothermic reaction
- Rate increased
If the pressure is increased what is the effect on the rate of reaching equilibrium?
- Moves in the direction of the fewest molecules of gas
- Rate increased (if reacting gases are present)
If the concentration of a reacting substance increase what is the effect on the rate of reaching equilibrium?
- Moves in the direction away from the reacting substance
- Rate increased
If a catalyst is added what is the effect on the rate of reaching equilibrium?
- The equilibrium position is not changed
- Rate increased
What is the order of reactivity?
Potassium
Sodium
Calcium
Magnesium
Aluminium
Zinc
Iron
(Hydrogen)
Copper
Silver
Gold
Metal + steam >
Metal oxide + hydrogen
Metal + water >
Metal hydroxide + hydrogen
Metal + acid >
Salt + hydrogen
In the reactions between metals and water/steel/acids, are the metals oxidised or reduced? Is the water oxidised or reduced?
Metal – oxidised
Water – reduced
How does a metals reactivity relate to its tendency to form cations?
The higher up a metal is in the reactivity series, the greater the tendency to form cations
The lower down the metal is, the greater it’s resistance to oxidation
Which metals react with water?
Potassium
Sodium
Calcium