A history of killing pain: First used in the 5th century, aspirin is the most widely used drug in the world, with more than 100 billion tablets consumed annually.

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RUBBER — C₅H₈
Natural rubber has been gathered from the sap of plants for centuries. But rubber only began to be used widely after 1839, when Charles Goodyear found a way to make it strong, durable and elastic. In 1931 U.S. chemist Elmer Bolton developed a synthetic version, and in 2005 we produced 21 million tonnes, with tyres and tubes accounting for 56 per cent of consumption. Other applications include gloves, rubber bands and balloons. Even some rockets and missiles are powered by synthetic, rubber-based fuels.

SILICON DIOXIDE — SiO₂
As the principal component in glass, silicon dioxide was used as early as 5000 BC. All the panes of glass in the world today cover about four billion square metres. Glass has also been essential for test tubes, telescopes, microscopes, mirrors and camera lenses.

POLYETHYLENE — (C₂H₄)_N
By far the most popular plastic, polyethylene is used in grocery bags, artificial joints and plastic bottles. It's even found in chewing gum. In fact, polyethylene is so ubiquitous that it's hard to imagine life without it. But in 1933 when English chemists Eric Fawcett and Reginald Gibson discovered it, they thought of it as nothing more than a waste product. Over 70 years later, more than 60 million tonnes of polyethylene are made each year; but there is a downside, as much of it ends up in landfill where it takes hundreds of years to degrade.

DDT — C₁₄H₉C_l5
In the 1950s and 1960s, DDT was used to eliminate malaria from Europe and North America in a program that, according to the World Health Organisation, saved an estimated 25 million lives. However, as early as the 1940s scientists had begun expressing concern over hazards associated with the use of DDT, and extensive research has since implicated the organochlorine insecticide in the poisoning of humans, animals and the environment. As a result, its use has been banned or restricted in many countries.

MORPHINE — C₁₇H₁₉NO₃
A potent painkiller, morphine was first isolated by German pharmacist Friedrich Sertürner in 1804. To this day, it remains the most important drug used to minimise suffering in terminally ill patients, particularly cancer sufferers. No other drug is as long-lasting and effective at managing severe pain. Despite this, 80 per cent of the world's population has access to just six per cent of the world's supply. Morphine is more widely distributed in the form of the illicit drug heroin, with an industry estimated at nearly A$100 billion annually.

AMMONIA — NH₃
In the early 20th century, the world's growing population couldn't find enough ammonia to fertilise all its crops. Due to the discovery of a technique to mass-produce ammonia, called the Haber process, an estimated two billion people are not starving today. We produce 100 million tonnes of ammonia for fertiliser each year, but it is also an important ingredient in explosives.