ACS CHEMISTRY GENERAL EXAM| QUESTIONS AND ANSWERS|
LATEST EXAM UPDATE 2025/2026
Layout of an element (mass # & atomic #) -CORRECT ANSWER
atomic number = -CORRECT ANSWER # of protons
mass number = -CORRECT ANSWER # of protons + neutrons
the number of protons in a neutral atom will equal the -CORRECT ANSWER
# 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
LATEST EXAM UPDATE 2025/2026
Layout of an element (mass # & atomic #) -CORRECT ANSWER
atomic number = -CORRECT ANSWER # of protons
mass number = -CORRECT ANSWER # of protons + neutrons
the number of protons in a neutral atom will equal the -CORRECT ANSWER
# 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
