The atomic theory is that all matter is made up of tiny units or particles called atoms. This theory describes the characteristics, structure and behavior of atoms as well as the components that make up atoms. Furthermore, the theory states that all elements are made up of identical atoms.Know More
The atomic theory is a theory in the study of chemistry that states atoms are the building blocks of matter. Atoms contain protons, neutrons and electrons. Protons, which have a positive charge, and neutrons are found in the nucleus of the atom. Electrons, which have a negative charge, orbit the nucleus.
According to the atomic theory, all elements contain atoms. The difference is the number of protons, electrons and neutrons in that atom. For instance, hydrogen contains one proton and one electron but no neutrons. Oxygen, on the other hand contains eight protons, electrons and neutrons. The difference in protons, electrons and neutrons determines the stability and the other properties of any particular element. These elements are grouped according to their atomic masses, which depend on the number of protons and neutrons in each of the atoms. Because oxygen has more protons and neutrons than hydrogen, it has a higher atomic mass.Learn more in Chemistry
In 1905, Albert Einstein published an analysis in which he devised a mathematical way to predict the size of both atoms and molecules. At the time, the science of atoms was still in its infancy, but Einstein's test was crucial in leading the way towards testing the reality of atoms.Full Answer >
Dalton's atomic theory states four critical truths about atoms: firstly, everything is made up of atoms and atoms cannot be destroyed. Secondly, all atoms within a single element are identical. Thirdly, compounds are formed from two or more different kinds of atoms. Finally, chemical reactions rearrange atoms.Full Answer >
Dmitri Mendeleev published his periodic table of elements in 1869. His table arranged the known elements according to their chemical properties and in order of their relative atomic mass. This created several gaps in the periodic table and allowed him to predict eight other undiscovered elements correctly.Full Answer >
In 1896, French scientist Antoine Henri Becquerel discovered radioactivity which was an early contribution to atomic theory. He discovered this phenomenon while experimenting with uranium and a photographic plate.Full Answer >