1. © Copyright Pearson Prentice Hall Structure of the Nuclear Atom > Slide 1 of 25 4.2 Subatomic Particles Three kinds of subatomic particles are: ___________________________ ___________________________.

2. Slide 2 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles Electrons In 1897, the English physicist J. J. _____________ (1856–1940) discovered the ____________ which are ________________ charged _____________ particles. 4.2

3. Slide 3 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles Thomson performed experiments that involved passing __________ ______________ through gases at low pressure. The result was a glowing beam, or _____________ __________, that traveled from the ___________ to the _______________. 4.2

4. Slide 4 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles A cathode ray is deflected by a magnet. 4.2

5. Slide 5 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles A cathode ray is deflected by electrically charged plates. 4.2 Cathode Ray Tube

6. Slide 6 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles Thomson concluded that a cathode ray is a ___________ of _____________ which are parts of the ___________ of all ____________. 4.2

7. Slide 7 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles Protons and Neutrons In 1886, Eugen Goldstein (1850–1930) observed a cathode-ray tube and found rays traveling in the direction opposite to that of the cathode rays. He concluded that they were composed of positive particles. Such ____________ ________________ subatomic particles are called ____________. 4.2

8. Slide 8 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles In 1932, the English physicist James __________________ (1891–1974) confirmed the existence of yet another subatomic particle: the ____________. _____________ are subatomic particles with ___ ___________ but with a mass nearly equal to that of a ____________. 4.2

9. Slide 9 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom Subatomic Particles Table 4.1 summarizes the properties of electrons, protons, and neutrons. 4.2

10. Slide 10 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom The Atomic Nucleus J.J. Thompson and others supposed the atom was __________ with __________ charged material and the ______________ were _________ _______________ throughout. _________ ______ This model of the atom turned out to be short-lived, however, due to the work of Ernest ____________ (1871–1937). 4.2

11. Slide 11 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom The Atomic Nucleus Rutherford’s Gold-Foil Experiment In 1911, Rutherford and his ____________ at the University of Manchester, ___________, directed a narrow beam of _________ __________ at a very thin sheet of __________ foil. 4.2

12. Slide 12 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom The Atomic Nucleus Rutherford’s Gold-Foil Experiment 4.2

13. Slide 13 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom The Atomic Nucleus Alpha particles scatter from the gold foil. 4.2

14. Slide 14 of 25 © Copyright Pearson Prentice Hall > Structure of the Nuclear Atom The Atomic Nucleus The Rutherford Atomic Model Rutherford concluded that the atom is mostly _______ ___________. All the ________ charge and almost all of the ________ are ____________ in a small region called the ____________. The ___________ is the _________ __________ _____________ of an atom and is composed of ____________ and ________________. 4.2

15. © Copyright Pearson Prentice Hall Structure of the Nuclear Atom > Slide 15 of 25 The Atomic Nucleus In the nuclear atom, the ________ and ______________ are located in the nucleus. The _____________ are distributed around the _____________ and occupy almost all the _______________ of the atom. 4.2