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Michigan State University
CEM 141 CEM 141 Exam 3 Questions and
Answers 2026 Latest Update
Differentiate between properties of atoms, nano-particles, and larger
macroscale materials. Explain why is it that atoms don't have macroscopic
properties like melting point, boiling point, and color, while macroscopic
materials do (and can be identified by them). Ans: The properties of new
substances depend on its molecular structure - the properties are emergent
For molecules to melt they interact with other molecules. It would not be
possible to melt a single atom/molecule.
Explain the force and energy changes that occur when two atoms approach
each other and form a bond. Explain why a third body (another atom or
molecule) is (almost always) needed to form a stable bond. (Think back to
what we learned in Chapter 1. Ans: A third atom will absorb some of the
energy thus lowering the energy between to atoms allowing the two atoms
to form a stable bond.
What determines whether a bond or interaction is stable? Explain how
temperature influences the stability of bonds and interactions Ans: The
stability of atoms depends on whether or not their outer-most shell is filled
with electrons. If the outer shell is filled, the atom is stable.
If you put enough energy (heat/temperature) in, the bond will break and the
atoms connected by that bond will fly apart.
Compare and contrast the molecular orbital bond model and the valence
bond model. What are the similarities? What are the differences Ans: ...
Valence Bond Theory Ans: two orbitals combine to form a bond between
two atoms
© 2026 All rights reserved
Michigan State University
CEM 141 CEM 141 Exam 3 Questions and
Answers 2026 Latest Update
Differentiate between properties of atoms, nano-particles, and larger
macroscale materials. Explain why is it that atoms don't have macroscopic
properties like melting point, boiling point, and color, while macroscopic
materials do (and can be identified by them). Ans: The properties of new
substances depend on its molecular structure - the properties are emergent
For molecules to melt they interact with other molecules. It would not be
possible to melt a single atom/molecule.
Explain the force and energy changes that occur when two atoms approach
each other and form a bond. Explain why a third body (another atom or
molecule) is (almost always) needed to form a stable bond. (Think back to
what we learned in Chapter 1. Ans: A third atom will absorb some of the
energy thus lowering the energy between to atoms allowing the two atoms
to form a stable bond.
What determines whether a bond or interaction is stable? Explain how
temperature influences the stability of bonds and interactions Ans: The
stability of atoms depends on whether or not their outer-most shell is filled
with electrons. If the outer shell is filled, the atom is stable.
If you put enough energy (heat/temperature) in, the bond will break and the
atoms connected by that bond will fly apart.
Compare and contrast the molecular orbital bond model and the valence
bond model. What are the similarities? What are the differences Ans: ...
Valence Bond Theory Ans: two orbitals combine to form a bond between
two atoms
© 2026 All rights reserved
