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Antoine Lavoisier
French chemist.
Became the father of modern chemistry.
He established the Law of Conservation of Mass.
He demonstrated that air is composed of two parts, one of which combines with metals to form calxes.
He demonstrated that the "air" responsible for combustion was also the source of acidity. -
The Law of Conservation of Mass
Established in 1789 by French Chemist Antoine Lavoisier.
States that mass is neither created nor destroyed in any ordinary chemical reaction.
Or more simply, the mass of substances produced (products) by a chemical reaction is always equal to the mass of the reacting substances (reactants). -
Dalton's Atomic Theory
Dalton concluded that evaporated water exists in air as an independent gas. -
John Dalton
He was born in September 6, 1766, in Eaglesfield, England.
In 1803 he revealed the concept of Dalton’s Law of Partial Pressures.
Also in the 1800s, he was the first scientist to explain the behavior of atoms in terms of the measurement of weight.
Dalton's theory was based on the premise that the atoms of different elements could be distinguished by differences in their weights.
Dalton died July 26, 1844 in Manchester, England. -
Dmitri Mendeleev
He formulated the Table of the Elements listing them by their atomic weight and grouping them into 'families' with similar characteristics. -
Ernest Rutherford
Ernest Rutherford publishes his atomic theory describing the atom as having a central positive nucleus surrounded by negative orbiting electrons.
This model suggested that most of the mass of the atom was contained in the small nucleus, and that the rest of the atom was mostly empty space. -
democritus
Born: about 460 BC in Abdera, Thrace, Greece
He became an English shool teacher when barely 12 years old.
In the year 1897 Joseph John Thomson totally changed the view of an atom by discovering electron.
Died: about 370 BC -
J.J. Thomson
Thomson was born in a suburb of Manchester, England, in 1856.
He became a proffessor at Trinity College.
In 1897 he discovered the electron.
He died in Cambridge in 1940. -
Cathode Ray Tube
Look at any glowing neon sign or any ‘old-fashioned’ television set, and you are looking at the modern descendants of the cathode ray tube. Later and improved cathode ray experiments found that certain types of glass produced a fluorescent glow at the positive end of the tube. With more experimentation, researchers found that the ‘cathode rays’ emitted from the cathode could not move around solid objects and so traveled in straight lines, a property of waves. -
Plum Pudding Atomic Model.
an atom model proposed by JJ Thomson, the physicist who discovered the electron.
It is also known as the Chocolate Chip Cookie or Blueberry Muffin Model.
you can imagine a plum pudding wherein the pudding itself is positively charged and the plums, dotting the dough, are the negatively charged electrons. -
Robert Millikan
Robert Andrews Millikan was born on the 22nd of March, 1868, in Morrison, Ill.
His earliest major success was the accurate determination of the charge carried by an electron, using the elegant "falling-drop method"; he also proved that this quantity was a constant for all electrons. -
Gold Foil Experiment!
Rutherford began to notice that alpha particles would not always behave in accordance to the plum pudding model of an atom when fired at a piece of gold foil. These observations stimulated further research that was eventually published in 1911 and has been known ever since as Rutherford's Gold Foil Experiment. -
Electron Cloud Model
An electron cloud is a visual model of the most probable locations of electrons in an atom. The cloud is denser where you will probably find an electron. The electron cloud model is used to describe the possible locations of electrons around the nucleus. -
Henry Moseley
Moseley was the first to clear and scientifically justify the atomic number studying X-ray spectra of chemical elements. -
Niels Bohr
He completed his theory of atomic structure. -
Bohr Planetary Model
This model was proposed by Niels Bohr.
The Bohr Model is an approximation to quantum mechanics that has the virtue of being much simpler. -
Quantum Mechanical Model
The quantum mechanical model was constructed by Erwin Schrödinger.
It correctly defines the electrons’ movement with relation to the nucleus. -
James Chadwick
An English Nobel laureate in physics awarded for his discovery of the neutron.
Born: October 20, 1891, Bollington
Died: July 24, 1974, Cambridge. -
Erwin Schrodinger
He shared with Dirac the Nobel Prize for 1933. -
Rutherford Model
Ernest Rutherford publishes his atomic theory describing the atom as having a central positive nucleus surrounded by negative orbiting electrons.
