Download Chapter 4: Energy Guided Reading

Name ____________________________________________ Date _______________ Period ______________
Chapter 17: Properties of Atoms and the Periodic Table- Key
Read the indicated sections and answer the following questions. They are IN ORDER from the text.
Page 506-511
1. What are the particles that make up the atom and where are they located? Particles that make up atoms
include protons and neutrons, which are located in the nucleus, and electrons, which are located in a
cloud surrounding the nucleus.
2. Explain how models can simplify science? Models are less expensive to build than the actual item and
they allow the study of things that are difficult to visualize (too big/small/time)or duplicate.
Page 512-515
3. Where is the majority of the mass of an atom located? In the nucleus. Protons and neutrons are much
larger than electrons.
4. Which element is an atom with six protons in the nucleus? Carbon
5. Uranium-238 (atomic mass) has 92 protons (atomic number). How many neutrons does it have? 146
neutrons (the formula is: (atomic mass - atomic # = # of neutrons).
6. Using Figure 8 at the top of pg 515, Explain why these atoms are isotopes. These atoms are isotopes
because they have the same number of protons but different numbers of neutrons.
Page 516-524
7. How did Mendeleev organize his periodic chart? He arranged the elements by increasing atomic mass
and aligned them in columns based on chemical and physical properties.
8. How is the modern periodic table arranged? By atomic number.
9. How many electrons are needed to fill the outer energy level of sulfur? Two additional electrons.
10. Using Figure 11, Explain what the elements in the last column share in relation to their outer energy
levels. Each element in the last column has a full outer-energy level.
11. Why do element in a group undergo similar chemical reactions? All members of a group have the same
number of electrons in their outer energy level.
12. What are the properties of the elements located on the left side of the periodic table? With the exception
of hydrogen, the elements on the left side of the table are metals, which are solids at room temperature,
shiny, and good conductors of heat and electricity. Hydrogen is an exception to these properties.