ACS CHEMISTRY FINAL EXAM 2025-2026
SPRING SESSION QUESTIONS AND
ANSWERS GRADED A+.
Layout of an element (mass Number & atomic Number) - Correct Answer ->>
atomic number = - Correct Answer ->> Number of protons
mass number = - Correct Answer ->> Number of protons + neutrons
the number of protons in a neutral atom will equal the - Correct Answer ->> Number of
electrons
how to find the correct number of neutrons - Correct Answer ->> mass number -
atomic number
Forms of the same elements that differ in amount of neutrons - Correct Answer ->>
isotopes
What particle, if lost from the nucleus, would NOT cause a change in the atomic
number? - Correct Answer ->> a neutron because it has no charge
When alpha particles were shot at a metal foil target, most passed through without
deflections, while others deflected at large angles. What did this suggest to Rutherford?
- Correct Answer ->> that the atoms of the metal were mostly empty space, while the
nucleus consisted of most of the mass which included highly condensed positive
particles (which caused the deflection).
An atom has a valence shell configuration of 1s1. To which group of elements on the
periodic table does it belong? - Correct Answer ->> IA
alkali metals
electromagnetic spectrum - Correct Answer ->>
The greater the wavelength of a photon..? - Correct Answer ->> the lower its frequency
The greater the frequency of a photon...? - Correct Answer ->> the shorter its
wavelength
,Light energy formula - Correct Answer ->>
What does C in the light energy formula represent? - Correct Answer ->>
Give the ground-state electron configuration of an atom in the second period - Correct
Answer ->> 1s2 2s1
Electrons configuration rule that states electrons do not pair until they have to. (put one
electrons in each electron domain then pair up) - Correct Answer ->> Hund's rule
An experimental phenomena associated with atoms having unpaired electrons - which
states such substances are attracted to magnetic fields - Correct Answer ->>
Paramagnetism
Which drop in energy level results in the greatest emission of energy? - Correct Answer
->> n=2 to n=1
quantum numbers - Correct Answer ->>
What do the 4 quantum numbers stand for? - Correct Answer ->> n =
energy level l = (n-1)
ml -l to l
mn 1/2 or -1/2 (spin)
List the quantum numbers for the s, p, d, and f orbitals - Correct
Answer ->> s 1,0,0 p 2, 1, -1-0-1
d 3, 2, -2--1-0-1-2
f 4, 3 -3--2--1-0-1-2-3
, Py orbital - Correct Answer ->>
Which element is represented by X - Correct Answer ->> Chromium
What two subatomic particles have the most mass, but occupy very little of the
volume of an atom - Correct Answer ->> protons and neutrons
Define Isoelectronic - Correct Answer ->> Having the same amount of electrons
How does a sodium ion differ from a sodium atom? - Correct Answer ->> the sodium ion
has fewer electrons
two or more compounds with the same formula but a different arrangement of atoms
in the molecule and different properties - Correct Answer ->> isomer
two or more different physical forms in which an element can exist. Graphite,
charcoal, and diamond are all of carbon. - Correct Answer ->> allotropes
What makes up an alpha particle? - Correct Answer ->> 2 protons and 2 neutrons
What did Millikan discover from his oil drop experiments? - Correct Answer ->> the
magnitude of the charge on an electron
Periods vs Groups - Correct Answer ->>
when an atom of an electropositive atom becomes an ion it..? - Correct Answer ->>
becomes larger
Nearly all the mass in an atom is located because both &
are located there, and each of these particles have a mass larger than the -
Answer- inside the
nucleus protons &
neutrons electron
Classify the following as an element, compound, or mixture. If it is a mixture, decide if
it is a homogeneous or heterogeneous mixture.
1 Sugar
SPRING SESSION QUESTIONS AND
ANSWERS GRADED A+.
Layout of an element (mass Number & atomic Number) - Correct Answer ->>
atomic number = - Correct Answer ->> Number of protons
mass number = - Correct Answer ->> Number of protons + neutrons
the number of protons in a neutral atom will equal the - Correct Answer ->> Number of
electrons
how to find the correct number of neutrons - Correct Answer ->> mass number -
atomic number
Forms of the same elements that differ in amount of neutrons - Correct Answer ->>
isotopes
What particle, if lost from the nucleus, would NOT cause a change in the atomic
number? - Correct Answer ->> a neutron because it has no charge
When alpha particles were shot at a metal foil target, most passed through without
deflections, while others deflected at large angles. What did this suggest to Rutherford?
- Correct Answer ->> that the atoms of the metal were mostly empty space, while the
nucleus consisted of most of the mass which included highly condensed positive
particles (which caused the deflection).
An atom has a valence shell configuration of 1s1. To which group of elements on the
periodic table does it belong? - Correct Answer ->> IA
alkali metals
electromagnetic spectrum - Correct Answer ->>
The greater the wavelength of a photon..? - Correct Answer ->> the lower its frequency
The greater the frequency of a photon...? - Correct Answer ->> the shorter its
wavelength
,Light energy formula - Correct Answer ->>
What does C in the light energy formula represent? - Correct Answer ->>
Give the ground-state electron configuration of an atom in the second period - Correct
Answer ->> 1s2 2s1
Electrons configuration rule that states electrons do not pair until they have to. (put one
electrons in each electron domain then pair up) - Correct Answer ->> Hund's rule
An experimental phenomena associated with atoms having unpaired electrons - which
states such substances are attracted to magnetic fields - Correct Answer ->>
Paramagnetism
Which drop in energy level results in the greatest emission of energy? - Correct Answer
->> n=2 to n=1
quantum numbers - Correct Answer ->>
What do the 4 quantum numbers stand for? - Correct Answer ->> n =
energy level l = (n-1)
ml -l to l
mn 1/2 or -1/2 (spin)
List the quantum numbers for the s, p, d, and f orbitals - Correct
Answer ->> s 1,0,0 p 2, 1, -1-0-1
d 3, 2, -2--1-0-1-2
f 4, 3 -3--2--1-0-1-2-3
, Py orbital - Correct Answer ->>
Which element is represented by X - Correct Answer ->> Chromium
What two subatomic particles have the most mass, but occupy very little of the
volume of an atom - Correct Answer ->> protons and neutrons
Define Isoelectronic - Correct Answer ->> Having the same amount of electrons
How does a sodium ion differ from a sodium atom? - Correct Answer ->> the sodium ion
has fewer electrons
two or more compounds with the same formula but a different arrangement of atoms
in the molecule and different properties - Correct Answer ->> isomer
two or more different physical forms in which an element can exist. Graphite,
charcoal, and diamond are all of carbon. - Correct Answer ->> allotropes
What makes up an alpha particle? - Correct Answer ->> 2 protons and 2 neutrons
What did Millikan discover from his oil drop experiments? - Correct Answer ->> the
magnitude of the charge on an electron
Periods vs Groups - Correct Answer ->>
when an atom of an electropositive atom becomes an ion it..? - Correct Answer ->>
becomes larger
Nearly all the mass in an atom is located because both &
are located there, and each of these particles have a mass larger than the -
Answer- inside the
nucleus protons &
neutrons electron
Classify the following as an element, compound, or mixture. If it is a mixture, decide if
it is a homogeneous or heterogeneous mixture.
1 Sugar
