STSE - Electronic Technology
By: Jessica S
What is a tablet (iPad) made of?
Elements that make up the device
Cobalt (Co): Also found in the battery
Rare Earth Metals (located in period 4,5,6 and group 3 in the periodic table with the atomic number 21, 39, and 57-71): Used to produce the different colours on the screen. They are also used for other purposes. Some are listed below.
Neodymium (Nd): Found in the magnets in the iPad.
Cerium (Ce) & Oxygen (O): The rare earth metal and the non-metal combine to form an ionic compound called cerium oxide that polishes the glass on the iPad. Oxygen itself makes the touch screen and other unique features possible.
Aluminum (Al): The material for the outer shell of the device to protect the inner compartment and prevent it from breaking.
Silicon (Si): Used for the memory chip.
Gold (Au) & Copper (Cu): Used to make the camera. Copper is also used for the wiring inside the iPad.
Tungsten (W): Used for the vibration feature.
Tantalum (Ta): Located in some microchips and maintains electricity in the device.
Silver (Ag) & Platinum (Pt): Used for the main logic board.
Mining of the elements
Cobalt (Co): Cobalt is a by-product when refining nickel. There are also large amounts of cobalt in manganese nodules in the ocean floor but this extraction method is too expensive. In the U.S., Minnesota has the largest nickel deposits which also means large amounts of cobalt.
Neodymium (Nd): Neodymium is extracted from minerals such as monazite and bastnasite. Large amounts of this element is present in the Earth's crust (about 38mg/kg). Some countries that mine it are Brazil, India, and Sri Lanka.
Cerium (Ce): This element is also extracted from minerals such as monazite and bastnasite. Monazite is found on India's beaches and bastnasite is found in Southern California.
Aluminum (Al): It is the third most abundant element in the Earth's crust. Aluminum comes from an ore called Bauxite that exists near the Earth's surface as flat layers. They are usually extracted by open-pit mining.
Silicon (Si): It is the second most abundant element in the Earth's crust. Silicon is mainly extracted from sand because there is a large amount and it is easy to mine and process.
Gold (Au): A common method of extraction is the placer method. This is formed when moving water erodes gold out of lode deposits. The heavy gold sinks to the bottom of the river and accumulates in the sand when the water slows down. Miners can easily access the gold. Gold is also a by-product of copper and silver mining.
Copper (Cu): Most of the time, this element is mined in open-pit mines because it's a less costly method. A more expensive method is to extract copper from deep-sea nodules created by volcanic activity. Chile produces 33% of the world's export of copper and is the largest producer but copper can also be found in Indonesia, Peru, and the U.S.
Tungsten (W): Tungsten is extracted from the ores of scheelite and wolframite. Some amount of tungsten is recovered through recycling tungsten products. Large tungsten reserves are located in Canada and Russia.
Tantalum (Ta): Tantalum is extracted from minerals such as columbite and tantalite. In the U.S., 20% of the tantalum is from recycling. Countries like Kazakhstan, Thailand, and Canada export this element.
Silver (Ag): Two thirds of the world's silver can be extracted from lead, zinc, and copper ore deposits. The other third is a by-product of gold. The largest producers of silver include Canada, Peru, and Mexico.
Platinum (Pt): This element is extracted from sulfides (thin layers of metal ores). Mafic igneous rocks which contain large quantities of iron and magnesium contain sulfide ores. In the ores, platinum usually exists as tiny pieces.
The Kennecott Bingham Canyon Mine in Utah where copper is mined.
Physical and chemical properties of aluminum
The element that I've chosen is aluminum.
Physical Properties:
Aluminum is a metal so it has metal properties. It has a silvery white colour and has lustre (shiny) which makes the iPad look polished and attractive. It is very light but also strong at the same time with a density of 2.7g/mL which is perfect for a protective shell for the iPad. Aluminum is ductile and malleable which is actually useful. If it is dropped, the case will not break and will only dent which still makes it usable. If a brittle material was used, the case would shatter into pieces easily. Also, this element has a high melting point of 660°C so even when it is used on hot summer days, the case will not melt off.
Chemical Properties:
Even though aluminum is highly reactive, it will combine with air to form an ionic compound called aluminum oxide (AlO). This acts like a protective layer and will prevent further corrosion (rusting). This property maintains the shiny appearance of the iPad.
Recycling
Apple's robot, "Liam".
Diagrams of Aluminum
Bohr Rutherford Diagram
Bohr Rutherford Diagram
Lewis Dot Diagram
Aluminum forming other compounds
Aluminum reacts easily and forms compounds with:
Bromine (Br): Aluminum Bromide - AlBr
Nitrogen (N): Aluminum Nitride - AlN
Sulphur (S): Aluminum Sulphide - Al2S3
Chlorine (Cl): Aluminum Chloride - AlCl3
Fluorine (F): Aluminum Fluoride - AlF3
*The numbers in the compounds could not be typed as a subscript*
These compounds are all ionic. This is because they are composed of a metal and a non-metal. Aluminum is the metal and the other element in each compound is a non-metal.