Metals Flashcards
(22 cards)
What is an ore?
Ore’s contain enough metal to make it economical to extract the metal. An ore is different to a rock. Ores are mined and may be concentrated before the metal is extracted and purified.
How do you get pure metals?
Most metals are found in compounds that require chemical reactions to extract the metal.
What is reduction?
The removal of oxygen from a compound.
What is smelting?
For example, copper-rich ores, heating the ores in a furnace
How can you purify a metal?
By electrolysis
What elements cannot be extracted from their ores by reduction with carbon?
Aluminium and titanium, current methods of extraction are expensive because there are many stages in the processes, therefore large amounts of energy is needed
What are the two new ways to extract copper from low grade ores?
Copper can be extracted by phytomining or bioleaching
What is phytomining?
The process of extraction of metals from ores using plants
What is bioleaching?
Process of extraction of metals from ores using microorganisms
Why should we recycle metals?
We should recycle metals because extracting them uses limited resources and is expensive in terms of energy and effects on the environment
What is the difference between iron from the blast furnace and steel?
Iron impurities make it brittle so it has limited uses. There is less carbon in steel than iron from the blast furnace.
What is an alloy?
An alloy is a mixture of metals or metals and non-metals. Alloys can be designed to have improved properties for specific uses.
What are steels?
Most iron is converted into steels. Steels are alloys since they are made up of metals and non-metals. Low-carbon steels are easily shaped, high carbon steels are hard, and stainless steels are resistant to corrosion.
What are some properties of metals in the central block of the periodic table?
They are known as transition metals. They are good conductors of heat and electricity and can be bent or hammered into shape. They are useful as structural materials and for making things that must allow heat or electricity to pass though them easily.
What are some good properties of copper?
Copper is a good conductor of electricity and heat, can be bent but is hard enough to be used to make pipes or tanks and copper does not react with water.
Why are aluminium and titanium useful metals?
Because they have low density and are resistant to corrosion.
What are some good sources of carbon?
Conde, charcoal and wood
How are metals extracted if they are less reactive than carbon?
From their oxides by reduction with carbon
How are metals that are more reactive than carbon extracted?
By electrolysis of molten compounds. The use of large amounts of energy in the extraction of these metals makes them expensive.
What is the process called where oxygen is removed?
Reduction
How can copper be obtained from solutions of copper salts?
By electrolysis or by displacement using scrap iron - during electrolysis positive ions move towards the negative electrode
How can copper be extracted?
From its ores by chemical processes that involve heat or electricity- copper rich ores are being depleted and traditional mining and extraction have major environmental impacts
