ACS CHEMISTRY GENERAL EXAM
QUESTIONS AND ANSWERS GRADED A+
2025/2026
Layout of an element (mass # & atomic #) - ANS
atomic number = - ANS # of protons
mass number = - ANS # of protons + neutrons
the number of protons in a neutral atom will equal the - ANS # of electrons
how to find the correct number of neutrons - ANS mass number - atomic number
Forms of the same elements that differ in amount of neutrons - ANS isotopes
What particle, if lost from the nucleus, would NOT cause a change in the atomic number? -
ANS 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? - ANS 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).
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,An atom has a valence shell configuration of 1s1. To which group of elements on the periodic
table does it belong? - ANS IA
alkali metals
electromagnetic spectrum - ANS
The greater the wavelength of a photon..? - ANS the lower its frequency
The greater the frequency of a photon...? - ANS the shorter its wavelength
Light energy formula - ANS
What does C in the light energy formula represent? - ANS
Give the ground-state electron configuration of an atom in the second period - ANS 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) - ANS Hund's rule
An experimental phenomena associated with atoms having unpaired electrons - which states
such substances are attracted to magnetic fields - ANS Paramagnetism
Which drop in energy level results in the greatest emission of energy? - ANS n=2 to n=1
quantum numbers - ANS
What do the 4 quantum numbers stand for? - ANS n = energy level
l = (n-1)
ml -l to l
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, mn 1/2 or -1/2 (spin)
List the quantum numbers for the s, p, d, and f orbitals - ANS 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 - ANS
Which element is represented by X - ANS Chromium
What two subatomic particles have the most mass, but occupy very little of the volume of an
atom - ANS protons and neutrons
Define Isoelectronic - ANS Having the same amount of electrons
How does a sodium ion differ from a sodium atom? - ANS 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 - ANS isomer
two or more different physical forms in which an element can exist. Graphite, charcoal, and
diamond are all ________ of carbon. - ANS allotropes
What makes up an alpha particle? - ANS 2 protons and 2 neutrons
What did Millikan discover from his oil drop experiments? - ANS the magnitude of the charge
on an electron
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
QUESTIONS AND ANSWERS GRADED A+
2025/2026
Layout of an element (mass # & atomic #) - ANS
atomic number = - ANS # of protons
mass number = - ANS # of protons + neutrons
the number of protons in a neutral atom will equal the - ANS # of electrons
how to find the correct number of neutrons - ANS mass number - atomic number
Forms of the same elements that differ in amount of neutrons - ANS isotopes
What particle, if lost from the nucleus, would NOT cause a change in the atomic number? -
ANS 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? - ANS 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).
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,An atom has a valence shell configuration of 1s1. To which group of elements on the periodic
table does it belong? - ANS IA
alkali metals
electromagnetic spectrum - ANS
The greater the wavelength of a photon..? - ANS the lower its frequency
The greater the frequency of a photon...? - ANS the shorter its wavelength
Light energy formula - ANS
What does C in the light energy formula represent? - ANS
Give the ground-state electron configuration of an atom in the second period - ANS 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) - ANS Hund's rule
An experimental phenomena associated with atoms having unpaired electrons - which states
such substances are attracted to magnetic fields - ANS Paramagnetism
Which drop in energy level results in the greatest emission of energy? - ANS n=2 to n=1
quantum numbers - ANS
What do the 4 quantum numbers stand for? - ANS n = energy level
l = (n-1)
ml -l to l
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, mn 1/2 or -1/2 (spin)
List the quantum numbers for the s, p, d, and f orbitals - ANS 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 - ANS
Which element is represented by X - ANS Chromium
What two subatomic particles have the most mass, but occupy very little of the volume of an
atom - ANS protons and neutrons
Define Isoelectronic - ANS Having the same amount of electrons
How does a sodium ion differ from a sodium atom? - ANS 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 - ANS isomer
two or more different physical forms in which an element can exist. Graphite, charcoal, and
diamond are all ________ of carbon. - ANS allotropes
What makes up an alpha particle? - ANS 2 protons and 2 neutrons
What did Millikan discover from his oil drop experiments? - ANS the magnitude of the charge
on an electron
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
