PPT-The Atom Rutherford’s Model of the Atom

Rutherford proposed that most of the mass of the atom was concentrated at the atoms center Rutherfords Model of the Atom Rutherfords experiment suggested that an atoms positive charge is concentrated in the center of the atom . At the end of this lesson, you need to draw . a diagram for each model showing the evolution of atomic theory:. ". Plum-Pudding" Model. Rutherford . Atom. Rutherford-Bohr . Atom. Charge-Cloud . Model. Ernest Rutherford. Determined the structure of the atom. First to split the atom. Hans Geiger . Inventor of the Geiger counter to measure radiation. Ernest Marsden. Found that a few scattered alphas at angle over 140 degrees from the beam. Democritus. This is the Greek philosopher Democritus who began the search . for a description of matter more than 2400 years ago. He asked:. Could matter be divided into smaller and smaller pieces . (around 400 BCE). Democritus thought matter could be divided into. . smaller and smaller pieces until a . single indivisible . particle is reached. . He named this particle the . atom. He proposed that atoms are of different sizes, in constant motion, and separated by empty spaces.. Edan Bainglass. Jose Chavez. Kennedy Izuagbe. After his discovery of alpha particle emissions from a radioactive isotope of Radon gas, for which he was awarded the 1898 Nobel prize in Chemistry, Rutherford spent a considerable amount of time and effort into their investigation. Textbook Pages 4-5. Lesson Objectives. Appreciate that there are various models to illustrate atomic structure. Know that early models of atomic structure predicted that atoms and ions with noble gas electron arrangements should be stable. Page 162. Super Model. Start a new thread/topic. Learning Target: How can you determine the structure of something you cannot see?. Update TOC. Super Model. Read Intro p. 162-163. Since we can’t see an atom, we are going to use different types of models to help us visualize atoms.. Review for Quiz. Match the Atomic Model to the Person who designed the model.. Use the Models Above . Niels. Bohr. John Dalton. Ernst Rutherford. J.J. Thomson. Niels. Bohr - D. John Dalton - A. Ernst Rutherford - C. DO NOW:. 1. 2. 3. 4. The Greek Concept of . Atomos. : . The . Indivisible Atom. . Around 440 BC, Leucippus originated the atom concept.. His pupil, Democritus (c460-371 BC) extended it . There are five major points to their atomic idea.. Five Experiments You Should Know. J. J. Thomson’s Cathode Ray. English physicist J. J. Thomson studied electrical discharges in partially evacuated tubes called . cathode-ray tubes. . He found that when high voltage was applied to the tube, a “ray” he called a . FP7-Science-in-Society-2012-1, Grant Agreement N. 321403. Geiger & Marsden's results. 2. FP7-Science-in-Society-2012-1, Grant Agreement N. 321403. Explore. Draw this to scale.... 1mm = 10 counts ?. . Constituents . of the atom. J.J. Thomson. (1856-1940) . . In 1897 J.J. Thomson discovered the . electron. . This is a tiny negatively charged particle that is much, much smaller than any atom. He said that the tiny negatively charged electrons must be embedded in a cloud of positive charge. Thomson imagined the electrons as the bits of plum in a plum pudding, rather like currants spread through a Christmas pudding.. Our view of the atom has changed over time. 2. Aristotle . (460 B.C. – 370 B.C.). emphasized that nature consisted of four elements: air, earth, fire, and water. did not believe in discontinuous or separate atoms, but felt that matter was continuous. Known as the “Laughing Philosopher”. “Nothing exists except atoms and empty space; everything else is opinion.”. Created term “. atomos. ” which literally means “not cut” or indivisible.