Download Physical Science Chapter 4 Study Guide mod 5

Physical Science Chapter 4 Study Guide
Name: _______________________________
The mass number of an atom is the number of protons
and neutrons in the atom.
1.
2. True or false: Electrons can be found between energy
levels? False
3. What is an atom’s nucleus made of? Protons neutrons
and electrons What kind of charge does it have? neutral
4. When does an electron jump to a new energy level?
When the electron gains or loses energy
5. List three key components of Dalton’s atomic theory.
All atoms of a given element are exactly alike, atoms of
different elements join to form compounds, atoms can
be divided
6. If an element has 22 protons, 24 neutrons, and 22
electrons, what is its mass number? 46 (atomic mass=
number of protons + number of neutrons)
7. An element with different isotopes has a different
neutrons (also, atomic mass)
8. An atom has a charge that is generally neutral
(because it has Equal #s of protons and electrons)
9. The atomic number of an atom is the same as the # of
protons
10. Rutherford’s model determined that an atom’s
positive charge is concentrated in the atom’s center.
11. True or false: Neutrons have a positive charge? False
12. Thomson discovered that an atom contains
negatively charged particles (electrons).
13. What did Thomson use to make his discovery about
the atom? Cathode ray
14. Thomson determined that atoms could be divided.
15. Why is it that atoms have no electric charge? They
are neutral because they have the same # of protons and
electrons
16. According to the modern atomic theory, is it possible
for us to determine an electron’s exact position? no
17. What does a mole describe? Measures how many
particles are in a substance
18. Why was Democritus’s original atomic theory
revised? No evidence to convince or support his claims
19. Which subatomic particle carries a negative charge?
electrons
20. Why was Dalton’s atomic theory accepted? He had
evidence to support claims
21. Describe Rutherford’s atomic model. The mass is in
the center of the cell (nucleus)
22. How do isotopes affect an element’s average atomic
mass? The number of neutrons are different so it
changes the mass
23. Why do atoms have no electric charge in spite of the
fact that they are made of charged particles?
They are neutral, same # of protons and electrons
24. Describe how ions are formed. When an atom gains
or loses one or more electrons the charge changes (more
electrons= negative; fewer electrons= positive)
25. Pretend you are looking at a periodic table. How do
you find the number of protons, neutrons, and electrons
for a given element? Atomic number: number of protons
Atomic mass: protons + neutrons
Neutral atom: protons=electrons
Positive: protons>electrons
Negative: protons<electrons