Hemistry Excel highschool final exam 2023 questions and
answers
A chemist is assigned the task of preparing gold for the manufacture of jewelry. The
chemist knows that pure gold is too soft for use in jewelry. She decides to mix the gold
with some silver. When she analyzes the metal mixture, she finds that the gold content
is the same in all parts of the mixture. Which of the following has the chemist produced?
an alloy of gold and silver
Which of the following is a physical property?
boiling point
Which of the following gases will have the slowest rate of effusion?
carbon dioxide (M = 44 g/mol
A student wants to develop a way to contain a plasma. The student thinks that she can
take advantage of one of the properties of a plasma to contain it in a magnetic field.
Which property might that be?
Plasmas consist of charged particles.
A closed flask contains a mixture of three gases: argon, oxygen, and helium. The
pressure in the flask is measured to be 640 mmHg. If the partial pressures of argon and
oxygen are equal and the partial pressure of helium is half the partial pressure of argon,
what is the partial pressure of helium?
128 mmHg
Which reaction would result in a change in odor, indicating a chemical change has
occurred?
frying an egg
A scientific artist is assigned the task of drawing an illustration depicting particles of a
solid. Which of the following best describes the drawing the illustrator should make?
spheres closely packed in a regular geometric pattern and vibrating in place
A student stirs the elements copper and sulfur together and then heats them in a test
tube. After heating, the material in the tube does not have the chemical or physical
properties of either copper or sulfur. The material in the test tube is most likely
a compound made of copper and sulfur chemically bonded to each other
Which pressure measurement describes the lowest gas pressure?
95,000 Pa
If a gas occupies a volume of 0.75 L at 130 kPa pressure, what pressure would the gas
exert if it were placed in a 4.0-L container at the same temperature?
24 kPa
What did the gold foil experiment demonstrate?
the density of mass in the nucleus
In the photoelectric effect, light of a certain frequency causes ejection of an electron
from a substance. If a different frequency of light is used, the photoelectric effect is not
observed even when the light intensity is increased. Which of the following statements
about light is fundamental to the explanation for these observations?
Light can be described as a stream of photons, which are particles of light.
, An atom of uranium, whose atomic number is 92, transforms in nature to an atom of
thorium plus a nucleus of helium, whose atomic number is 2. What is the atomic number
of thorium?
90
An ion of oxygen contains eight protons and has a charge of 2-. What must occur for
this ion to become a neutral oxygen atom?
It must lose two electrons.
Which of the following statements is associated with the quantum theory of atomic
structure?
Each electron has a defined amount of energy that can be defined by a set of numbers.
What experimental work led Dalton to his atomic theory?
partial pressure gas laws
A student is making a diagram to illustrate the hydrogen atom according to the Bohr
model. She wants to show how the model correlates to the hydrogen emission
spectrum. Which of the following should be true about the diagram drawn by the student
if the diagram is to be accurate?
The diagram should show several energy levels with arrows pointing in the direction
from the lower to the higher levels to show the movement of hydrogen's one electron in
creating the emission lines.
Which of the following characters is a possible azimuthal quantum number?
01
Which of the following statements provides information about the azimuthal quantum
number of an electron?
An electron is in a p orbital in an atom.
Which particle is a neutron most equal to in mass?
a proton
The Bohr model of the atom proposed that _____.
electrons have a fixed amount of energy
What is the atomic symbol for tin?
None of the listed answers are correct
How many valence electrons does the element boron have?
three
Which valence electrons in tin are responsible for determining how it interacts with other
elements?
electrons in the 5s and 5p orbitals
Which element has the atomic symbol Pb?
lead
Which of the following determines the identity of an element?
its atomic number
Typically, if the valence orbital of an atom is full, the atom is _____.
relatively stable
The transition metals contain valence electrons in an inner _____ orbital, that can
contain up to ten electrons.
d
In what orbital would the two valence electrons of strontium be found?
5s
answers
A chemist is assigned the task of preparing gold for the manufacture of jewelry. The
chemist knows that pure gold is too soft for use in jewelry. She decides to mix the gold
with some silver. When she analyzes the metal mixture, she finds that the gold content
is the same in all parts of the mixture. Which of the following has the chemist produced?
an alloy of gold and silver
Which of the following is a physical property?
boiling point
Which of the following gases will have the slowest rate of effusion?
carbon dioxide (M = 44 g/mol
A student wants to develop a way to contain a plasma. The student thinks that she can
take advantage of one of the properties of a plasma to contain it in a magnetic field.
Which property might that be?
Plasmas consist of charged particles.
A closed flask contains a mixture of three gases: argon, oxygen, and helium. The
pressure in the flask is measured to be 640 mmHg. If the partial pressures of argon and
oxygen are equal and the partial pressure of helium is half the partial pressure of argon,
what is the partial pressure of helium?
128 mmHg
Which reaction would result in a change in odor, indicating a chemical change has
occurred?
frying an egg
A scientific artist is assigned the task of drawing an illustration depicting particles of a
solid. Which of the following best describes the drawing the illustrator should make?
spheres closely packed in a regular geometric pattern and vibrating in place
A student stirs the elements copper and sulfur together and then heats them in a test
tube. After heating, the material in the tube does not have the chemical or physical
properties of either copper or sulfur. The material in the test tube is most likely
a compound made of copper and sulfur chemically bonded to each other
Which pressure measurement describes the lowest gas pressure?
95,000 Pa
If a gas occupies a volume of 0.75 L at 130 kPa pressure, what pressure would the gas
exert if it were placed in a 4.0-L container at the same temperature?
24 kPa
What did the gold foil experiment demonstrate?
the density of mass in the nucleus
In the photoelectric effect, light of a certain frequency causes ejection of an electron
from a substance. If a different frequency of light is used, the photoelectric effect is not
observed even when the light intensity is increased. Which of the following statements
about light is fundamental to the explanation for these observations?
Light can be described as a stream of photons, which are particles of light.
, An atom of uranium, whose atomic number is 92, transforms in nature to an atom of
thorium plus a nucleus of helium, whose atomic number is 2. What is the atomic number
of thorium?
90
An ion of oxygen contains eight protons and has a charge of 2-. What must occur for
this ion to become a neutral oxygen atom?
It must lose two electrons.
Which of the following statements is associated with the quantum theory of atomic
structure?
Each electron has a defined amount of energy that can be defined by a set of numbers.
What experimental work led Dalton to his atomic theory?
partial pressure gas laws
A student is making a diagram to illustrate the hydrogen atom according to the Bohr
model. She wants to show how the model correlates to the hydrogen emission
spectrum. Which of the following should be true about the diagram drawn by the student
if the diagram is to be accurate?
The diagram should show several energy levels with arrows pointing in the direction
from the lower to the higher levels to show the movement of hydrogen's one electron in
creating the emission lines.
Which of the following characters is a possible azimuthal quantum number?
01
Which of the following statements provides information about the azimuthal quantum
number of an electron?
An electron is in a p orbital in an atom.
Which particle is a neutron most equal to in mass?
a proton
The Bohr model of the atom proposed that _____.
electrons have a fixed amount of energy
What is the atomic symbol for tin?
None of the listed answers are correct
How many valence electrons does the element boron have?
three
Which valence electrons in tin are responsible for determining how it interacts with other
elements?
electrons in the 5s and 5p orbitals
Which element has the atomic symbol Pb?
lead
Which of the following determines the identity of an element?
its atomic number
Typically, if the valence orbital of an atom is full, the atom is _____.
relatively stable
The transition metals contain valence electrons in an inner _____ orbital, that can
contain up to ten electrons.
d
In what orbital would the two valence electrons of strontium be found?
5s
