Download Unit IV Review Guide: Atomic Structure and Nuclear Reactions

CP Chemistry
Review for Chapter 4 Test: The Structure of the Atom
4.1 Early ideas of the Atom
● Know how each of the following influenced atomic theory: Democritus,
Dalton, Thompson, Rutherford
● Be able to explain Dalton’s atomic theory and how parts of it have since been
proven wrong
4.2 Defining the Atom
● Be able to explain how the Gold Foil Experiment led to the discovery of the
nucleus
● Define the proton, electron, and electron in terms of location, charge, and
mass
4.3 How atoms Differ
● Be able to relate atomic number and mass number to the number of
protons, neutrons and electrons
● Understand how isotopes are similar and different
● Understand and calculate average atomic mass
4.4 Unstable Nuclei and Radioactive Decay
● Understand and define the three types of radioactive decay in terms of
composition and penetrating ability.
● Be able to write nuclear decay equations
24.2 Radioactive Decay
● Show how the strong nuclear force hold the nucleus together
● Understand the concept of half-life
● Use the a table to perform half-life calculations
24.3 Nuclear Reactions
● Explain the difference between nuclear fusion and fission
● Explain how a nuclear power plant works and describe the parts of the
reactor and power plant.
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Practice Problems
1. State the main points of Dalton’s Atomic Theory in your own words. Which parts
of Dalton’s theory were later found to be false? Explain why.
2. How was the charge distributed in the plum pudding model of the atom?
3. Which subatomic particle was discovered by researchers working with
cathode-ray tubes?
4. Briefly explain how Rutherford discovered the nucleus? Draw a diagram to help
explain.
5. How do isotopes of a given element differ? How are they the same?
6. Fill in the table below
Element
Cl
Atomic
Number
17
Mass Number
35
Cl
Zr
40
37
92
Protons
40
Neutrons
Electrons
Zr
50
17
2
7. How many electrons, protons and neutrons are contained in each atoms
a.
b.
8. Gallium, which has an atomic mass of 69.723 amu has two naturally occurring
isotopes, Ga-69 and Ga - 71. Which isotope occurs in greater abundance? Explain.
9. Silver has two isotopes: Ag - 107 has a mass of 106.905 amu and a percent
abundance of 52.00%. Ag - 109, which has a mass of 108.905 amu, and a percent
abundance of 48.00%. What is the average atomic mass of silver?
10. What change in mass number occurs when a radioactive atom emits an alpha
particle? A beta particle? A gamma particle?
11. Write the balanced nuclear reaction for the
a. alpha decay of boron - 10
b. beta decay of cesium - 137
c. alpha decay of americium- 241
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d. beta decay of neptunium - 239
12. What is the strong nuclear force? On which particles does it act?
13. The half-life of tritium H-3 is 12.3 years. If 48.0 mg is released from a nuclear
power plant during the course of a mishap, what mass will be left after
a. 5 half lives
14. Static charge can interfere with the production of plastic product by attracting
dust and dirt. To reduce it, manufactures expose the area to polonium - 210, which
as a half-life of 138 days.
a. How much of a 25.0 g sample is left after 2 half lives?
16. Explain the purpose of control rods in a nuclear reactor.
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Oldies but goodies!!!
1. What is the difference between the independent and dependent variable?
2. How many significant figures does a number have? (example: .00670)
3. Calculations with correct significant figures (example: 2.65 × .035)
4. Converting one metric unit to another metric unit (keeping in mind significant
figures - example: 350.0 mL to L)
5. Is a change a chemical or physical change? (example: snow melting, iron rusting,
...)
6. Percent by mass problems (example: what is the percent of oxygen in a
compound that contains 12.6 g of oxygen and 46.3 g of nitrogen, and 5.67 g of
hydrogen.
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