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ACS Chemistry general Exam 2026
Latest Questions and Answers (100%
Expert Answers) A+
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
© 2026
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).
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
The greater the wavelength of a photon..? [ Ans: ] the lower its frequency
The greater the frequency of a photon...? [ Ans: ] the shorter its
wavelength
,2
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
What do the 4 quantum numbers stand for? [ Ans: ] n = energy level
l = (n-1)
ml -l to l
© 2026
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
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
, 3
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
when an atom of an electropositive atom becomes an ion it..? [ Ans: ]
becomes larger
© 2026
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 ______ [ Ans: ] 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
2 Spaghetti Sauce
3 Phosphorus [ Ans: ] 1 compound, not a mixture
2 mixture, heterogenous
ACS Chemistry general Exam 2026
Latest Questions and Answers (100%
Expert Answers) A+
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
© 2026
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).
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
The greater the wavelength of a photon..? [ Ans: ] the lower its frequency
The greater the frequency of a photon...? [ Ans: ] the shorter its
wavelength
,2
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
What do the 4 quantum numbers stand for? [ Ans: ] n = energy level
l = (n-1)
ml -l to l
© 2026
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
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
, 3
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
when an atom of an electropositive atom becomes an ion it..? [ Ans: ]
becomes larger
© 2026
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 ______ [ Ans: ] 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
2 Spaghetti Sauce
3 Phosphorus [ Ans: ] 1 compound, not a mixture
2 mixture, heterogenous
