Understanding matter The four elements Despite the atomists theories most ancient philosophers thought that instead of many types of atoms there were just four basic substances or elements earth fire air and water The idea of these four elements carried on for many centuries into medieval and Renaissance times However in the 1600s a new age of detailed scientific study was born and people began to question the four elements A new approach Scientists did careful experiments mixing combining and breaking down different types of substances to see what they were really made of It became clear that there had to be more than just four ingredients making up the universe Brilliant Boyle One of the most important scientists of the time was Irish experimenter Robert Boyle He argued that matter was made of atoms after all and that there were many different types of basic atoms and elements not just four He wrote a book called The Sceptical Chymist published in 1661 explaining that atoms moved around and joined together in groups to make different substances Robert Boyle Date of birth January 25 1627 Place of birth Lismore Ireland Greatest achievement Boyle revolutionized the science of matter turning it from superstitious alchemy into modern evidence based chemistry Interesting fact Boyle was also interested in anatomy and finding out how the bodies of animals and humans worked but he couldn’t bear to dissect bodies as it made him feel ill Date of death December 31 1691 10
Alchemy Boyle’s work grew out of alchemy an ancient practice of trying to treat or change everyday substances such as lead and stone to create more valuable substances such as gold It didn’t work but it did involve a lot of experimentation and resulted in some useful discoveries Boyle said that scientists should do proper careful experiments to find clear evidence of what matter was made of and how it worked This was really the beginning of the modern science of chemistry the study of substances and how they behave join break apart and change Boyle studied many things including how gases behave under pressure and how freezing and burning worked Thanks to Boyle old myths were replaced with proper experiments and evidence and the idea of four elements was swept away The search began for the real elements the many different types of atoms This 19th-century painting by William Fettes Douglas shows an alchemist at work You can see his chemical-mixing equipment and a potion he is concocting Breakthrough Robert Boyle’s book The Sceptical Chymist 1661 and his experiments marked a new direction in the study of the science of matter 11
Atoms and elements Amazing discoveries Boyle’s breakthrough ideas influenced many other scientists Through the 1700s they devised lots of experiments to find out more and more about matter They especially wanted to discover the different types of atoms that existed and the elements or basic substances that they made as oxygen and carbon They showed how the elements combined to make substances such as carbon dioxide The elements didn’t always have the same names as they do now for example carbon dioxide was known as fixed air and hydrogen inflammable air But that was about to change In experiments to make metals react with acids British chemist Henry Cavendish released the element hydrogen He studied this new gas and found that it was lighter than air and burned easily He went on to prove that hydrogen and oxygen reacted together to make water so water was definitely not a pure element It was made of hydrogen and oxygen atoms Other experimenters including Joseph Black and Joseph Priestley isolated and tested various elements such As hydrogen is lighter than air it was eventually used to fill airships and make them fly But its highly flammable qualities led to terrible disasters such as the loss of this airship the Hindenburg in 1937 12
Lavoisier The king of chemistry was Frenchman Antoine Lavoisier Working in the late 1700s he discovered many elements or types of atoms and made a list of 33 elements that had been found so far He came up with a naming system and gave oxygen hydrogen and other elements their modern names He set out rules for chemical reactions and experiments so that all chemists could follow the same practices and compare their results He also helped to set up the metric measuring system that scientists still use today Matter stays the same Lavoisier defined a very important rule in chemistry the Law of Conservation of Matter This states that when chemicals react together and substances change matter is never created nor destroyed it simply changes form One can assume in principle that in every operation there is an equal quantity of matter before and after the operation Antoine Lavoisier explains that chemical reactions neither destroy nor create matter This picture of Antoine Lavoisier and his wife also a chemist shows them studying the gases that make up the earth’s atmosphere Breakthrough Antoine Lavoisier gathered together his own and other scientists work and set out a system of rules names measurements and practices for the science of chemistry This made it easier for chemists to share and compare their work and brought chemistry into the modern age 13
