Chapter 1. 1, 1.3-1.9 Flashcards Preview

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Flashcards in Chapter 1. 1, 1.3-1.9 Deck (15):
1

diatomic

2 atoms

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Ernest rutherford

carried out experiments to test Thompson plum pudding model

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Rutherford experiements

involved directing alpha particles at a thin sheet of metal foil

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Rutherford hypothesis

reasoned that if Thomson model was accurate the massive alpha particles should crash through the thin foil, expected alpha particles to travel through the foil with very minor deflections in their paths

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result of Rutherford experimenet

most particles went through, many were deflected at large angles, some were reflected, never hitting the detector

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conclusion of Rutherford experiment

knew puddingmodel could not be correct, large deflections could be caused only by a center of concentrated positive charge that contains most of atom's mass, most of the particles pass directly through the foil because the atom is mostly open space, the deflected alpha particles are those that had a close encounter with the positive center of the atom, few reflected the particles are those that made a direct hit on the positive center

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nucleus

1. its small size compared with overall size, accounts for almost all the atom's mass 2. extremely high dentistry, dramatically demonstrated by the fact that a piece of nuclear material about the size of a peace would have a mass of 250 million tons

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isotopes

atoms with same number of protons, but differnet number of neturons

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atomic number

number of protons

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mass number

number of proton and neutrons

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energy

ability to do work or produce heat, can be connected from one form to another, no energy is created or destroyed, can be divided into kinetic and potential energy

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work

force acting over a distance

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joule

fundamental unit of energy, kilogram meter squared per second square, used to describe energy

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mole

unit for describing numbers of atoms or molecules present 6.022 times 10 to the negative 23rd

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per mole

means that 6.022 times 10 to the negative 23rd are represented by the quantity in question