Extraction and uses of metals Flashcards
Explain, with reference to the structure, why neodymium is malleable and a good conductor of electricity.
- Neodymium ions are packed in layers
- Those ions can slide past each other
- They contain delocalized electrons
- These delocalized electrons can freely move
What does the reaction suggest about the reactivity of aluminum compared to the reactivity of iron? Explain your answer.
- Aluminium is more reactive than iron
- Aluminium displaces iron
What is meant by the term catalyst?
A substance that increases the rate of reaction
Explain why molybdenum is malleable
- Molybdenum ions are in layers
- positive ions slide over each other
Name the main ore used as the source of iron
Haematite
Identify the element and state its purpose in the extraction of aluminum
Element: Carbon
Purpose: Positive electrode
Identify the element and state its purpose in the extraction of iron
Element: Oxygen
Purpose: Production of heat
State one reason why cryolite is used in the extraction of aluminium
- To lower the temperature
Name two substances that must be present for iron to rust
- Water
- Oxygen
How does the method of painting prevent rusting to occur?
Prevents water from coming in contact with iron
Explain how this method of protection works, even when the surface of the zinc is scratched to expose the iron underneath.
- Zinc is more reactive than iron and therefore, corrodes in preference to iron
Why is aluminum not extracted by heating its oxide with carbon monoxide?
Aluminium is more reactive than carbon
Why is iron not extracted from its oxide using electrolysis?
Electricity is expensive
Suggest why distillation can be used to remove magnesium chloride from titanium
Magnesium chloride has lower b.pt
State two other methods used to prevent iron from rusting
- Painting
- Oiling/greasing
Name the main compound present in limestone
Calcium Carbonate
Why would lead not be suitable for use in the electrical circuits of a probe to land on Venus?
It has a low melting point
Why do metals higher in the reactivity series require electrolysis for extraction?
Metals higher in the reactivity series, such as those above carbon, are too reactive to be reduced by carbon. Therefore, electrolysis is needed for their extraction.
Provide an example of an alloy and its composition.
Brass, an alloy containing 70% copper and 30% zinc.
Explain why alloys are harder than pure metals.
Alloys have atoms of different sizes, disrupting regular arrangements and making it harder for layers to slide over each other
Describe the properties of mild steel and its use.
0.25% carbon, is soft and malleable, used in car body panels and wires.
Why is copper used in electrical wires?
Copper is a good conductor of electricity and malleable
Name a significant property of aluminum and its use in aeroplane bodies.
High strength-to-weight ratio (low density)
What is bacterial extraction in metal extraction processes?
Bacterial extraction occurs when bacteria absorb metal compounds, producing leachates containing the metals
Explain phytoextraction in metal extraction processes.
Phytoextraction involves:
- plants absorbing metal compounds through their roots
- concentrating them
- producing ash containing the metal when burned.
In metal extraction, how does the reactivity series influence the method of extraction?
The method of extraction is determined by the metal’s position in the reactivity series.
- Higher-placed metals require electrolysis
- Lower-placed metals can be extracted by heating with carbon.
Why do unreactive metals like gold and platinum not require chemical extraction?
Unreactive metals are often found as the uncombined element
What is the definition of an ore?
An ore is a rock that contains enough of a metal to make it worthwhile extracting.
Why is magnalium harder than aluminum?
- Magnalium is an alloy, whereas aluminum is a metal
- Magnalium being the alloy is harder because the atoms of the mixed metals are different sized, disrupting the regular arrangement and making it harder for layers to slide over each other.
What is meant by the term alloy?
homogeneous mixture of two or more metals, or a metal and a non metal
