Name: ______
Chapter 11 Worksheet Packet
Section 1 Reading Guide (312-317) 1. The Greek philosopher Democritus thought that if you kept cutting something in half, you would eventually end up with a particle that could ______be cut.
2. The word atom is from the Greek word atomos, meaning “ ______”
3. True or false: Aristotle agreed with Democritus’s ideas. ______
4. Sketch below what Democritus’s idea of an atom may have looked like
5. What is an atom?
6. By the late 1700s, scientists had learned that elements combine in certain ______based on mass to form compounds.
7. Which scientist came up with the atomic theory? ______
8. What are the three main ideas of the atomic theory? a.
b.
c.
9. Sketch below what Dalton’s idea of an atom may have looked like
10. In 1897, a British scientist named J.J. Thomson showed that there are small ______inside the atom; this means that atoms can be divided into even smaller parts.
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 1 11. Looking at Figure 3 on page 314, add in the missing information to the diagram
12. What subatomic particle did Thomson discover? ______
13. What is an electron?
14. What is the name for Thomson’s new model of an atom? ______
15. Sketch below what Thomson’s idea of an atom may have looked like
16. In your own words, explain what Rutherford’s experiment looked like.
17. What results did Rutherford see in his experiment? a. Most particles went through the gold foil b. Some of the particles were deflected (turned to one side) c. Some bounced straight back d. All of the above
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 2 18. Rutherford proposed that in the center of the atom is a tiny, extremely dense, positively charged part called the ______.
19. Sketch below what Rutherford’s idea of an atom may have looked like
20. Niels Bohr’s work focused on which subatomic particle? ______
21. Bohr’s model said that electrons move around the nucleus in certain paths, or ______.
22. Sketch below what Bohr’s idea of an atom may have looked like
23. What were the names of two scientists that contributed to the modern atomic theory? a.
b.
24. Was Bohr’s idea of electrons traveling around in paths correct? _____
25. According to the current atomic theory, there are regions inside the atom where electrons are like to be found. These regions are called ______.
26. Using Figure 8 on page 317 as a guide, label the diagram below
Atomic Models Worksheet (Modifiied from Unit5.org)
Directions: Fill in the blanks on the right with the information in the chart below.
Word List atom neutron Bohr nucleus Dalton proton Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 3 Democritus Rutherford destroyed subatomic particle electron substances electron cloud Thomson
More than 2000 years ago, the Greek philosopher __(1)__ proposed the existence of very small, indivisible particles, each of which was called a(n) __(2)__. The theory that such particles existed was supported, much later, by several different scientists. In 1803, a scientist by the name of __(3)__ came up with the atomic theory, which had three points to it: I. All substances are made of atoms. Atoms are small particles that cannot be created, divided, or __(4)__. II. Atoms of the same element are exactly alike, and atoms of different elements are different III. Atoms join with other atoms to make new __(5)__.
It was later proposed that the atom was not indivisible, but is made up of smaller particles, each of which is called a(n) __(6)__. These particles include the negatively-charged __(7)__, the positively- charged __(8)__; and the uncharged __(9)__. The small electrons were discovered by a scientists named __10)__, who created a model called the Plum Pudding model. The larger two particles are present in the __(11)__, or center, of the atom, which was discovered by __(12)__ in his gold foil experiment.
The Danish physicist __(13)__ proposed a model of the atom in which the electrons orbit the nucleus without losing energy. He called each possible orbit an electron level. Today, the modern atomic theory suggests that an electron’s position cannot be predicted, but the area where one is likely to be is a(n) __(14)__.
Section 2 Reading Guide (pages 318-324) 1. Give one example from page 381 that shows just how small atoms are
2. Look at figure 2 on page 319 to complete the information below
3. Elements join in a ______ratio according to their masses to form a compound.
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 4 4. What type of charge do protons have? ______
5. The SI unit used to express the masses of particles in atoms is the ______.
6. What type of charge do neutrons have? ______
7. Which subatomic particle(s)are found in the nucleus (circle any that are true) a. Proton b. Neutron c. Electron
8. Both the proton and the neutron have a mass of about ___ amu, which the mass of an electron is usually thought of as ____ amu.
9. To have a neutral charge, an atom has to have the same number of protons and ______.
10. Does an atom need to have equal number of protons and neutrons? _____
11. What is the atomic number?
12. The atomic number is always equal to the number of ______in an atom; it can be thought of as the identity of an atom.
13. What is an isotope?
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 5 14. Look at Figure 4 on page 321. What is different between the two pictures?
15. Each element has a ______number of isotopes that are found in nature.
16. ______atoms (isotopes) spontaneously fall apart after a certain amount of time. However, isotopes of an element share ______of the same chemical and physical properties.
17. What is the mass number?
18. How is the mass number useful tor telling isotopes apart?
19. Read the naming isotopes section on page 323. If I have a sample of Boron with 5 protons, 5 neutrons, and 5 electrons, how would I name this isotope? ______
20. What is atomic mass?
21. How is atomic mass different than atomic number?
22. List the four different forces in atoms and briefly describe them a. b. c. d.
Building Atoms worksheet (Modified from Elizabeth Scheidel’s worksheet: https://imoodle.district833.org/mod/resource/view.php?id=2352)
Directions: Below you will find the ten most common elements found in Earth’s crust. The element symbol has been given to you on your left. Using either pages 338-339 in your textbook or a handout of the periodic table, complete the chart below.
ATOMIC ELEMENT ELECTRON NEUTRON ATOMIC # WEIGHT / PROTON # NAME # # MASS
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 6 Isotope…or New Element? (Modified from Kim George’s worksheet)
For each problem you are given a pair of elements. Based on the information about each elements, please determine if they are different elements or isotopes of the same element.
1. Element D has 6 protons and 7 neutrons Element F has 7 protons and 7 neutrons
2. Element J has 27 protons and 32 neutrons Element L has 27 protons and 33 neutrons
3. Element x has 17 protons and 18 neutrons Element Y has 18 protons and 17 neutrons
4. Element Q has 56 protons and 18 neutrons Element R has 56 protons and 82 neutrons
5. Element T has an atomic number of 20 and an atomic mass of 40 Element Z has an atomic number of 21 and an atomic mass of 41
6. Element W has 8 protons and 8 neutrons Element V has 7 protons and 8 neutrons
7. Element P has an atomic number of 92 and an atomic mass of 238 Element S has 92 protons and 143 neutrons
Now, you need to identify each element and give it the proper isotope name.Use page 323 in your textbook for help, and pages 338-339 or a periodic table handout
Example: Element D has 6 protons, which makes it Carbon. Its mass number is 13, so the proper name is Carbon-13
Element F: ______Element J: ______Element L: ______Element X: ______
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 7 Element Y: ______Element Q: ______Element R: ______Element T: ______Element Z: ______Element W: ______Element V: ______Element P: ______Element S: ______
Acad Sci 9—Chapter 11 Packet 2012-2013 P a g e | 8