4.10 Using resources Flashcards
(28 cards)
What is a natural resource?
A material or substance found in nature that is used by humans, such as water, wood, fossil fuels, or minerals.
What is a finite resource?
A resource that is non-renewable and will eventually run out, such as fossil fuels, metal ores, and some minerals.
What is a renewable resource?
A resource that can be replaced at the same rate at which it is used, such as solar energy, wind power, or sustainably managed timber.
What is sustainable development?
Meeting the needs of the current generation without compromising the ability of future generations to meet their own needs.
How is potable water produced from fresh water sources?
By filtering the water to remove solids and sterilizing it to kill harmful microbes using chlorine, ozone, or ultraviolet light.
What is desalination?
A process used to produce potable water from seawater by removing dissolved salts through distillation or reverse osmosis.
What are the disadvantages of desalination?
It requires large amounts of energy, making it expensive and environmentally impactful in terms of carbon emissions.
What are the main stages in wastewater treatment?
Screening, sedimentation, aerobic biological treatment, and sometimes anaerobic digestion of sludge.
What is sludge and how is it treated?
Sludge is the solid waste from sedimentation; it is digested anaerobically by bacteria, producing biogas and fertilizer.
What is bioleaching?
A method of extracting metals using bacteria to produce solutions of metal ions from low-grade ores.
What is phytomining?
A method of metal extraction where plants absorb metal compounds from soil and are then burned to produce ash containing the metal.
Why are alternative methods like phytomining and bioleaching used?
Because traditional mining becomes uneconomical for low-grade ores, and these methods are less damaging to the environment.
What is corrosion?
The gradual destruction of a material (usually a metal) by chemical reactions with substances in the environment, such as oxygen and water.
How can corrosion be prevented?
By applying coatings such as paint, oil, plastic, or plating, or by using sacrificial protection (e.g., attaching a more reactive metal like zinc).
What is galvanising?
A corrosion prevention method where iron or steel is coated with a layer of zinc, which serves as both a barrier and a sacrificial metal.
What are alloys?
Mixtures of metals (or metals with non-metals) that are designed to have improved properties compared to pure metals.
Why are alloys used instead of pure metals?
Alloys are usually harder, stronger, or more corrosion-resistant than the pure metals they are made from.
What are the main components of bronze and what is it used for?
Bronze is an alloy of copper and tin, used in statues, medals, and decorative items.
What are the main components of brass and what is it used for?
Brass is an alloy of copper and zinc, used for musical instruments, plumbing fittings, and coins.
What is stainless steel and what are its properties?
An alloy of iron, carbon, and chromium or nickel, it is corrosion-resistant and used in cutlery, sinks, and medical instruments.
What are the two types of glass and how do they differ?
Soda-lime glass (made from sand, limestone, and sodium carbonate) is more common, while borosilicate glass (from sand and boron oxide) has a higher melting point.
What are composites?
Materials made from two or more materials with different properties, combined to produce a material with desirable properties from both.
Give examples of composites.
Fibreglass (glass fibres in a resin), carbon fibre (carbon fibres in a polymer matrix), concrete (sand, gravel, and cement), and wood (natural composite of cellulose and lignin).
What is a Life Cycle Assessment (LCA)?
A method to evaluate the environmental impact of a product throughout its entire life – from raw material extraction to disposal.
