Over the course of the last 5000 years, mankind’s knowledge has been constantly advancing. Chemistry, a branch of science, has experienced a tremendous leap and expansions since ancient Greek civilization. One of the major breakthroughs in the advancement in Chemistry was the creation of the Atomic theory, which laid a foundation for the modern-day Chemistry and future of science. The Atomic theory introduced the idea of atoms, which are defined as the discrete units of matter. There are five key scientists that significantly contributed to the Atomic model over a span of thousands of years. They are: Democritus, John Dalton, J.J. Thompson, Ernest Rutherford, and Niels Bohr.
The Atomic Theory is a theory that explains what matter is made of. The Atomic theory states that matter can’t be divided as it is made up of minute particles called atoms that cannot be separated. The very word atom is derived from the Greek word Atmos which means indivisible.
The field of science during the times of the Greeks have greatly influenced the modern world as one perceives it in the present day. The atomic theory has much responsibility for the relation of Greek thought and modern beliefs. Democritus was one of the fir4st Greek philosophers to explain the theory of the atom. He said that it was indivisible. Furthermore, he explained that each element is made of particles, and that change occurs by the transfer of the atoms. In comparison to the modern day atomic theory, Democritus had the correct notion as to the significance of the atom-it is indivisible. From the research done, Democritus’ idea of the atom did not directly influence the contemporary theory of the atom. The Greek
Democritus made the atomic theory widely known, which stated that the universe is composed of two elements: the atoms and the void in which these atoms exist and move. (More, 1646)
Around 2,500 years ago, Democritus and his partner Leucippus were the first ones to develop the atomic theory in written history. Their theory proposed that every kind of matter was made up of tiny particles, which were named atomos, which means that it is indivisible. This meant that Democritus and Leucippus thought there were little particles of everything, but, the next breakthrough in atomic theory wasn’t made until the early 1800s with a french chemist by the name of Antoine Lavoisier, he was the one who came up with the idea of the law of the conservation of mass, which states that matter stays the same even when it changes shape or form. Then, James Dalton said that all matter was made up of atoms, which were indivisible, and unbreakable.
The book contains the results of numerous experiments and establishes an early version of the Law of Conversation Mass. Jan Baptist van Helmont suggested that substances other than air and coined a name for them, gas, from the Greek word chaos. Next we get to a important breakthrough in making sense of the list of known chemical elements was Dmitri Mendeleev's, that discovered the first modern periodic table, or the periodic table of the elements. Mendeleev, who was a Russian chemist, felt like that there was some type of order to the elements and he spent more than thirteen years of his life finding and searching for more and more data and making the concept, initially with the idea of finding some of the order in the field for his students. I could go on and tell you more about the history before chemistry, but I think you get the point.
John Dalton wrote the modern atomic theory, a fundamental component of that is, the mole ratios of elements in a compound will be small whole numbers.
Around 1803 John Dalton, an English chemist developed the first useful atomic theory of matter. Amedeo Avogadro, the Italian chemist in 1811 published an article drawing the distinction between the atom and the molecule, which now is known as “Avogadro’s
At the beginning of the twentieth century a scientist called Albert Einstein had a special theory about atoms. His theory was that atoms had a lot of energy locked within them. After this theory was published scientists worked hard to prove that this theory was true. After thirty years of experiments they discovered that within the nucleus there is a lot of energy and splitting the atom would release it.
This information has not always been know to man though. Thankfully scientist such as J.J Thompson, Ernest Rutherford, and James Chadwick were able to perform experiments to shed more light on what the atom was made of. The electron was first found in 1897 by J.J Thompson; shortly after in 1911 the nucleus was discovered by Rutherford, leading to him later discovering the proton in 1919. Before James Chadwick discovered the neutron many scientists believed that there were additional protons in the nucleus, along with the equal number of electrons to cancel out the additional charge. Then in 1920 Rutherford thought that the protons plus the electrons made up a new particle but it was never confirmed. After a few years of study John Chadwick was able to discover the neutron through unidentified radiation experiments, one experiment in particular caught his eye Frédéric and Irène Joliot-Curie had studied unidentified radiation from beryllium as it hit a paraffin wax target. This experiment encouraged Chadwick to do some of his own experiments in 1932 which made him believe that the radiation ejected from beryllium was in fact a neutral particle about the mass of a proton. He also tried many other targets besides the paraffin wax, these included helium, nitrogen, and lithium. These experiments led Chadwick to find the the mass of the new particle was more than the proton, he also found out that the neutrons have no
Leucippus and Democritus discovered the atom(doc. 1). Ernest Rutherford split the atom and discovered that the atom is made of smaller particles and that atoms have a positively charged nucleus and largely empty space(doc. 1). Without Leucippus and Democritus, no one could expand on the idea of the atom and without Rutherford no one would have thought of the nucleus and what is inside the atom(doc. 1). Atoms are so small
The Ancient Greeks were the firsts to speculate on the composition of matter. They thought that it was possible that individual particles made up matter.
He stated that this was a mysterious force but never continued his research on it. Then in 460 B.C. there was a philosopher named Democritus. Democritus and his mentor Leocippus posed the question that if he broke bread into multiple pieces how many would breaks would it take until there was no more bread. He then was able to make a few theories being all matter was created of atoms and atoms are solid but not invisible. However, there was a man named Aristotle and many other philosophers who disagreed with Democritus and said matter was composed of four main elements. Earth, fire, air, and water. For example, a liquid was made of water and a stone was made of rock. Therefore, Democritus’s theory “ was rejected by Aristotle, one of the most influential philosophers of Ancient Greece; and the atomic theory was ignored for nearly 2,000 years.”(
The Discovery of the Atom first came from the Greeks which made a theory “The idea that all matter is made up of tiny, indivisible particles, or atoms, is believed to have originated with the Greek philosopher Leucippus of Miletus and his student Democritus of Abdera in the 5th century B.C. (The word atom comes from the Greek word atomos, which means “indivisible.”)” (InfoPlease Atomic theory)