Name ______________________________ Class __________________ Date __________________
Assessment
4.1 More Practice
Section: The Development of Atomic Theory
In the space provided, write the letter of the term or phrase that best completes
each statement or best answers each question.
____ 1. Democritus’s original atomic theory was revised because it
a. claimed matter is made of atoms. c. explained what electrons are.
b. claimed atoms could be divided. d. did not have a scientific basis.
____ 2. Which of these statements is not part of Dalton’s atomic theory?
a. Atoms cannot be divided.
b. Atoms of an element are alike.
c. Atoms are made of electrons.
d. Atoms of different elements form compounds.
____ 3. A subatomic particle that has a negative charge is called a(n)
a. molecule.
c. element.
b. electron.
d. compound.
____ 4. Who determined that atoms could be divided?
a. Democritus
c. Dalton
b. Thomson
d. Rutherford
____ 5. Thomson made his discovery about the atom during an experiment using
a. thermal energy.
c. cathode rays.
b. kinetic energy.
d. X rays.
____ 6. Thomson is responsible for discovering that an atom contains
a. electrons.
c. anodes.
b. molecules.
d. a nucleus.
____ 7. Which of the following statements not true?
a. Protons have a positive charge. c. Neutrons have no charge.
b. A nucleus has a positive charge. d. Neutrons have a negative charge.
____ 8. What is an atom’s nucleus made of?
a. protons and neutrons
c. only neutrons
b. only protons
d. anodes
____ 9. In _______________________ atomic model, negative electrons orbit the positively
charged nucleus.
a. Dalton’s
c. Rutherford’s
b. Thomson’s
d. Democritus’s
____ 10. Whose model determined that an atom’s positive charge is concentrated in the atom’s
center?
a. Rutherford’s
c. Democritus’s
b. Dalton’s
d. Thomson’s
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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Atoms
Name ______________________________ Class __________________ Date __________________
Assessment
4.2 More Practice
Section: The Structure of Atoms
In the space provided, write the letter of the term or phrase that best completes each statement or
best answers each question.
____ 1. What is the mass of 2.5 mol of Ca, which has a molar mass of
40 g/mol?
a. 2.5 g Ca
b. 20.0 g Ca
c. 40.0 g Ca
d. 100.0 g Ca
____ 2. What is the amount of nickel in moles, which has an average atomic mass of 58.7 u,
present in 525 g nickel?
a. 28.0 mol
b. 8.90 mol
c. 525 mol
d. 58.7 mol
____ 3. Avogadro’s number is useful for
a. counting atoms.
c. locating an atom’s electrons.
b. counting large objects.
d. None of the above
____ 4. What is the molar mass of an element with an average atomic mass of 9.012 u?
a. 6.022  1023 grams
c. 12.01 grams
b. 9.012 grams
d. 0.012 grams
____ 5. The charge of an atom is
a. positive.
b. neutral.
c. negative.
d. unbalanced.
____ 6. An iron atom has an atomic mass of 56. Its atomic number is 26. How many neutrons
does the iron atom have?
a. 30
b. 56
c. 26
d. 82
____ 7. How much effect do commonly found isotopes have on the average atomic mass of an
element?
a. less than rarely found isotopes c. same as rarely found isotopes
b. no effect on atomic mass
d. more than rarely found isotopes
____ 8. An element’s atomic number is equal to its number of
a. protons.
c. valence electrons.
b. neutrons.
d. protons and neutrons.
____ 9. Two different isotopes of an element have different
a. numbers of neutrons.
c. atomic numbers.
b. numbers of protons.
d. numbers of electrons.
____ 10. What is the mass number of an element that has 19 protons,
19 electrons, and 20 neutrons?
a. 19
c. 39
b. 20
d. 58
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science Spectrum
24
Atoms
Name ______________________________ Class __________________ Date __________________
Assessment
4.3 More Practice
Section: Modern Atomic Theory
In the space provided, write the letter of the term or phrase that best completes each statement or
best answers each question.
____ 1. A sodium atom, which has 11 electrons, has ____________ electron(s) in its third
energy level.
a. 0
b. 1
c. 2
d. 8
____ 2. Unlike the modern model of the atom, Bohr’s model states that
a. electrons move in set paths around the nucleus of an atom.
b. atoms cannot be divided into smaller parts.
c. electrons behave like waves.
d. electrons contain orbitals.
____ 3. Which of the following is not a type of orbital?
a. s
b. d
c. p
d. x
____ 4. An electron jumps to a new energy level (higher or lower) when
a. the atom becomes charged.
b. the atom becomes unstable.
c. the electron’s location is pinpointed.
d. the atom gains or loses energy.
____ 5. The number of energy levels filled in an atom is determined by
a. protons.
b. electrons.
c. neutrons.
d. photons.
____ 6. Which of the following statements is not true?
a. An s orbital can hold two electrons.
b. A d orbital can hold up to two electrons.
c. An f orbital can hold up to three electrons.
d. A p orbital can hold two electrons.
In the space provided, write the letter of the term or phrase that best matches each description.
a.
b.
c.
d.
____ 7. found in the outer energy level of a tome
____ 8. where electrons are likely to be found in an atom
____ 9. unit or quantum of light
____ 10. what happens to an electron when
it gains energy
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science Spectrum
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Atoms
orbital
valence electron
photon
excited state