-
100
Democritus
-came up with the idea that matter is composed of empty space through which atoms move.
-atoms are solid, homogeneous have different sizes and shapes
-different kinds of atoms have different sizes and shapes
410 BC -
100
aristotle
- one of the most influential philosophers. -wrote extensively on many subjects including politics, ethics, nature, physics, and astronomy.
- most of his writings have been lost through the ages
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Joseph Proust
Known for creating elements of water. also worked on weight of elements -
antione lavosier
compiled a list of elements known at hte time. The list contained 23 elements. Many of these elements such as silver, gold, carbon, and oxygen, were known since prehistoric times. -
William Crookes
noticed flashed that produced some form of radiation striking a light-producing coating that had been applied to the end of the tube. -
Dalton
-all matter is composed of extremely small particles called atoms
-all atoms of a given element are identical, having the same size, mass, and chemical properties. Atoms of a specific element are different from those of any other element. -
Amadeo Avagadro
was known for mocleur theroy. Also worked on the weight of mass voulmes of gases. -
invention of telephone
was created by alexander grahm bell. The first coversation was Come in here I want to see you. people could now talk to each other over the phone -
Invention of automobile
Was a vehicle that could be driven and was on four wheels -
Madame Curie
She did pinoneer research for radioactivity she also discovered two elements and also won a nobal peace prize -
Henri Becquerel
He was the one who discovered radioactivty and he won 3 nobal peace prize. -
J.J Thomsonn
He began a series of cathode ray tube experiments in the late 1890's to determine the ration of its charge to its mass. He then determined the charge to mass ration of the charged particle. -
max planck
began searching for an explanation as he studied the light emitted from heated objects. -
Robert Millikan
He determined the charge of an electron -
Ernest Rutherfed
Rutherfed worked on alph atoms and how they could be deflected throught objects. -
Henry mosaley
Discovered that atoms of each element contain a unique positive charge in their nulei. -
niels bohr
proposed that hydrogen atom has only certain allowabel energy states. The lowest alowable evergy state of an atom is called its ground state. when an atom gains evergy it is said to be in an excited state. -
werner heisenberg
concluded that it is impossible to make any measurement on an object without disturbing the object. -
louis debroglie
propoesd idea that eventually accounted for the fixed energy levels of bohr's model. -
Erwin Schrodinger
furthered the wave-particle theory proposed by debroglie. He derived an equation that treated the hydrogen atom's electron as a wave. -
Albert Einstein
Developed theroy of realtivity which is one of the two pillars of modern science. -
James chadwhick
showed that the nucleus also contained another subatomic partilce a neutral partilce call the neutron. -
World war II
Was a war that was fought between Germany, Japan, France, America -
Vietnam
was a war fought between America and Vietnam over a long period of time before America pulled out of the war
