PAPER 1 LAST MINUTE STUFF Flashcards
Why is an alloyed metal stronger than a pure metal?
- Pure metal atoms = all same size
- Layers slip over each other easily
- Alloy adds metals that are different sizes
How would you remember the reactivity series?
Please stop loudly calling me a careless zebra, instead try learning how copper saves gold
Name the reactivity series
Describe which metals will undergo which extraction methods
Describe how you would prepare a pure, dry sample of barium sulphate from a barium chloride solution
What is an alloy?
A mixture of metals
Why are alloyed metals stronger than pure metals?
- Pure metals all the atoms are the same size
- In a pure metal, the atoms slide over each other easily
- The other metal will disrupt the size of the pure metal
- This will prevent the atoms from sliding over each other
How are metals higher than carbon extracted?
Using electrolysis
Why are metals higher than carbon extracted using electrolysis instead of being heated with carbon?
- The metal is higher in the reactivity series / it is more stable
- Electrolysis is a very powerful means of reduction
- Carbon is not a strong enough reducing agent to produce the metal from its ore
- Carbon can’t displace the more reactive metal
Advantages of Bioleaching
Does not require high temperatures
Disadvantages of Bioleaching
- Toxic substances & sulfuric acid can be produced in the process
- Damage to the environment
Advantages of Phytoextraction
Can extract metals from contaminated soils
Disadvantages of Phytoextraction
- More expensive than mining some ores
- Growing plants dependant on weather conditions
Advantages of Phytoextraction & Bioleaching
- No harmful gases produced
- Causes less damage to the landscape than mining
- Conserves supplies of higher grade ores
disadvantages of Phytoextraction & Bioleaching
Very slow process
What is Bioleaching?
Uses bacteria grown on a low grade ore
What is a leachate?
A solution produced when water or another solvent passes through a mixture of substances and dissolves some of them
Describe bioleaching
- Bacteria produce a leachate
- Copper is extracted from the leachate by displacing using scrap (metal)
- It is then purified by electrolysis
What is Phytoextraction?
Involves growing plants that absorb metal compounds
—> Plants are burnt to form ash (metal is extracted from there)
Which metals are extracted by heating an ore with iron?
- Zinc
- Iron
- Copper
Which metals are found as a uncombined element?
Silver & Gold
What is an ore?
A rock that contains enough of a compound to extract a metal for profit
What is extraction?
The process of obtaining a metal from a compound
Which metals react violently with dilute acid?
- Potassium
- Sodium
Which metals react to form hydrogen & a metal hydroxide with cold water?
- Potassium
- Sodium
- Calcium
What does the metals Potassium, Sodium, Calcium produce when they react with cold water?
Hydrogen & metal hydroxide
Which metals react to form hydrogen & a salt solution with dilute acid?
- Calcium
- Magnesium
- Aluminium
- Zinc
- Iron
Which metals reacts very slowly with cold water?
- Magnesium
- Aluminium
- Zinc
- Iron
What does the metals Magnesium, Aluminium, Zinc, Iron produce when they react with steam?
Hydrogen & metal oxide
What does the metals Magnesium, Aluminium, Zinc, Iron produce when they react with cold water?
Nothing
Which metals react to form hydrogen & a metal oxide with steam?
- Magnesium
- Aluminium
- Zinc
- Iron
Which metals DOES NOT react with dilute acid?
- Copper
- Silver
- Gold
Which metals DOES NOT react with cold water or steam?
- Copper
- Silver
- Gold
Advantages of Recycling
- Natural reserves of metal ores will last longer
- Less pollution may be produced
- Mining can damage landscape - need for mining will be reduced
- Less waste metal ends up in landfill sites
- Less Co2
Disadvantages of Recycling
- High cost & energy needed for collecting, transporting & sorting metals to be recycled
- Can be more expensive & require more energy to recycle than to extract a new metal
What is a weak acid?
- Partially dissociates into ions
- Concentration of H+ ions is lower than expected
What salts are insoluble?
- Silver & lead chloride
- Lead, barium & calcium sulphate
- Most common carbonates
- Most common hydroxides
What salts are soluble?
What does this hazard symbol mean?
Oxidising
Makes flammable substances burn more fiercely
What does this hazard symbol mean?
Serious health hazard
Breathing difficulties
What does this hazard symbol mean?
Moderate health hazard
Skin irritation
What does this hazard symbol mean?
Corrosive
Damages skin & clothing
What does this hazard symbol mean?
Harmful to environment
Can cause damage to animal & plant life
What does this hazard symbol mean?
Toxic
Could cause death if swallowed
What does this hazard symbol mean?
Flammable
Catches fire easily
Purpose of hazard symbols
- Indicates the dangers associated with the substance inside
- Gives information about how to work safely with the substance in the laboratory
What is a precaution?
Something that can be done to reduce a risk of harm
Why is point B to C flat?
Intermolecular bonds between particles are being broken
—> Turning from solid to liquid
Explain why painting iron objects prevents corrosion
Why the exposed iron does not rust if it was galvanised with zinc & scratched so iron is exposed
Give two advantages for electroplating some metal objects
What happens to a chemical cell if its left on for a long period of time?
- Starts bright
- Gets dimmer
Why does the voltage of a chemical cell decrease over time?
Reactants are being used up
ADVANTAGES of hydrogen oxygen fuel cells
- Fuel cells can operate as long as reactants are supplied
- Water is the only product
- Fuel cells have a longer lifetime
DISADVANTAGES of hydrogen oxygen fuel cells
- Hydrogen is flammable
- Hydrogen is difficult to store - gas
- Fuel cells are expensive to manufacture
Describe titration
