Name: ___________________________
Date: __________ Period: _______
Write all of your answers on a separate sheet of paper. When applicable, write your answers in complete
sentences.
1. Dalton’s atomic theory stated that atoms of one element are different form atoms of another element.
Describe 2 of these differences.
2. According to Dalton’s atomic theory, what happens to atoms during a chemical reaction?
3. According to Dalton’s theory, which diagram(s) below represents a mixture? Why?
4. Which diagram(s) below represents a pure substance? Explain.
A
B
C
5. JJ Thomson experimented with a device called a _______________________________________.
6. Write 2 – 3 sentences that explain what Thomson learned as a result of his experiments with this device.
7. Draw in the path of the particles as
Thomson observed them pass through the
device below.
8. Write 2 – 3 sentences describing the
+
Experiment performed by Ernest
Rutherford.
9. What important information was learned
from Rutherford’s experiment
10. What are isotopes? Explain.
11. Fill in the chart below:
Name
Symbol
Atomic
Number
Number of
Protons
Number of
Neutrons
Carbon -
Mass
Number
Number of
Electrons
12
Mg
25
50
69
16
31
143
Sr
92
38
90
Neon - 20
Ge
73
12.
13.
14.
15.
What is the name for the model of the atom to the right?
Label all of the subatomic particles in this picture and include their charges.
Who discovered that electrons have a very small mass and a charge of -1?
What is the difference between the Bohr model and the Quantum
Mechanical Model of the atom?
16. For the following figure:
a. LABEL the following items on the diagram: neutrons, protons, electrons,
nucleus, + charge, - charge
b. How many electrons does this atom have?
c. How many protons does this atom have?
d. How many neutrons does this atom have?
e. What is its mass #?
f. What element is this? How do you know? What value(s) did you use?
g. Is this particular atom the most common isotope of this element?
How do you know?
17. Why are the atomic mass values on the periodic tables not whole numbers? Explain.
18. Complete the following table
Subatomic particle
Mass
Charge
location
1.
neutron
electron
Calculate the average atomic mass for Calcium based on the
Isotopes given below:
Isotope
Percent Abundance
2.
proton
Ca - 39
6%
Ca - 40
84%
Ca – 41
10%
Calculate the average atomic mass for Calcium based on the
isotopes given below:
Isotope
Percent Abundance
Ca - 39
11%
Ca - 40
84%
Ca – 41
5%
3. Why do you get different answers for questions 17 & 18? Explain.
4. Why are the atomic mass values on the periodic tables not whole numbers? Explain.
Complete the chart below by drawing models for the following elements:
Element
Bohr Model
Aufbau Diagram
Fluorine
Electron Configuration
Sodium
Answer the following questions in your textbook at home: Page 149
24, 26, 34, 36, 37
Problems: 22, 23,