CHEM 141 FINAL EXAM QUESTIONS &
ANSWERS RATED 100% CORRECT
The Greek's ideas about atoms were based more on philosophy than evidence. Which of their
ideas is still considered to be true and what is the evidence that now supports it?
1. The shapes of atoms determine their properties
2. Atoms are composed of mostly empty space
3. Atoms are the smallest piece of matter
BECAUSE
4. When alpha particles are shot at a piece of golf foil, most go straight through
5. Advanced microscopy techniques allow us to visualize atoms, but nothing smaller
6. Snowflakes are hexagonal because atoms of water are hexagonal
a. 1 and 5
b. 2 and 5
c. 1 and 6
d. 3 and 4
e. 2 and 4
f. 3 and 5 - correct answer ✔✔e. 2 and 4
The plum pudding model of the atom was in improvement over _____ model of the atom
because _____
1. Dalton's
2. Thomson's
3. Rutherford's
4. The cathode ray tube provided evidence for the existence of particles smaller than an atom
,5. The gold foil experiment provided evidence for a small, massive nucleus in the middle of the
atom
6. Isotopes are atoms of the same element with a different number of neutrons in the nucleus
a. 3 and 4
b. 1,2 and 5
c. 2 and 5
d. 1 and 6
e. 1 and 5
f. 1 and 4 - correct answer ✔✔f. 1 and 4
What evidence was used to disprove this statement from Dalton's Atomic Theory? All atoms of
an element are identical and have the same mass and properties
a. Electrons have a negative charge and were attracted to the plate with the positive charge
b. the existence of ions
c. protons are located in the nucleus of the atom
d. the existence of isotopes
e. The existence of electrons from the cathode ray tube experiment - correct answer ✔✔d. the
existence of isotopes
Was Dalton's atomic theory a scientific theory?
1. Yes
2. No
BECAUSE
3. It is based on available experimental evidence and scientific theory that can change when
new evidence becomes available
4. It is not completely correct, and a scientific theory cannot be proven false.
a. 1 and 3
, b. 2 and 3
c. 1 and 4
d. 2 and 4 - correct answer ✔✔a. 1 and 3
Consider the question: How much table salt will dissolve in a liter of water?
Is this question a scientific question?
a. Yes, because there is a scientific law that addresses this question
b. No, because an experiment testing this could not be repeated and thus be inclusive
c. No, because you can look up the answer to this question without doing an experiment
d. Yes, because you can design a repeatable experiment to gather data to answer the question -
correct answer ✔✔d. Yes, because you can design a repeatable experiment to gather data to
answer the question
Draw a good representation of molecules that are an element - correct answer ✔✔drawing
should consist of three atoms in a molecule
What can be said about energy when a bond or interaction is formed?
a. energy can either be absorbed or released depending on the strength of the interaction
b. energy is absorbed from the surroundings
c. energy is released from the system to the surroundings
d. there is no change in energy when a bond or interaction is formed - correct answer ✔✔c.
energy is released from the system to the surroundings
Which of the following are true for the electrostatic force:
1. Depends on mass
2. Depends on charges
3. Stronger than the gravitational force
ANSWERS RATED 100% CORRECT
The Greek's ideas about atoms were based more on philosophy than evidence. Which of their
ideas is still considered to be true and what is the evidence that now supports it?
1. The shapes of atoms determine their properties
2. Atoms are composed of mostly empty space
3. Atoms are the smallest piece of matter
BECAUSE
4. When alpha particles are shot at a piece of golf foil, most go straight through
5. Advanced microscopy techniques allow us to visualize atoms, but nothing smaller
6. Snowflakes are hexagonal because atoms of water are hexagonal
a. 1 and 5
b. 2 and 5
c. 1 and 6
d. 3 and 4
e. 2 and 4
f. 3 and 5 - correct answer ✔✔e. 2 and 4
The plum pudding model of the atom was in improvement over _____ model of the atom
because _____
1. Dalton's
2. Thomson's
3. Rutherford's
4. The cathode ray tube provided evidence for the existence of particles smaller than an atom
,5. The gold foil experiment provided evidence for a small, massive nucleus in the middle of the
atom
6. Isotopes are atoms of the same element with a different number of neutrons in the nucleus
a. 3 and 4
b. 1,2 and 5
c. 2 and 5
d. 1 and 6
e. 1 and 5
f. 1 and 4 - correct answer ✔✔f. 1 and 4
What evidence was used to disprove this statement from Dalton's Atomic Theory? All atoms of
an element are identical and have the same mass and properties
a. Electrons have a negative charge and were attracted to the plate with the positive charge
b. the existence of ions
c. protons are located in the nucleus of the atom
d. the existence of isotopes
e. The existence of electrons from the cathode ray tube experiment - correct answer ✔✔d. the
existence of isotopes
Was Dalton's atomic theory a scientific theory?
1. Yes
2. No
BECAUSE
3. It is based on available experimental evidence and scientific theory that can change when
new evidence becomes available
4. It is not completely correct, and a scientific theory cannot be proven false.
a. 1 and 3
, b. 2 and 3
c. 1 and 4
d. 2 and 4 - correct answer ✔✔a. 1 and 3
Consider the question: How much table salt will dissolve in a liter of water?
Is this question a scientific question?
a. Yes, because there is a scientific law that addresses this question
b. No, because an experiment testing this could not be repeated and thus be inclusive
c. No, because you can look up the answer to this question without doing an experiment
d. Yes, because you can design a repeatable experiment to gather data to answer the question -
correct answer ✔✔d. Yes, because you can design a repeatable experiment to gather data to
answer the question
Draw a good representation of molecules that are an element - correct answer ✔✔drawing
should consist of three atoms in a molecule
What can be said about energy when a bond or interaction is formed?
a. energy can either be absorbed or released depending on the strength of the interaction
b. energy is absorbed from the surroundings
c. energy is released from the system to the surroundings
d. there is no change in energy when a bond or interaction is formed - correct answer ✔✔c.
energy is released from the system to the surroundings
Which of the following are true for the electrostatic force:
1. Depends on mass
2. Depends on charges
3. Stronger than the gravitational force
