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Michigan State University
CEM 141 CEM 141 MSU Exam 1 Questions
and Answers 2026 Latest Update
The statement "If I add cold milk to hot coffee the temperature will
decrease," is a? Ans: Claim, always include an explanation and reasoning to
the claim.
Scientific Model Ans: Models are used to make testable predictions
How much is a picometer? Ans: 0.1 x 10^-12 meters
Atomic Force Microscopy/ Scanning Tunneling Microscopy Ans: Microscopes
that now allows us to view atoms.
Leaves are green in the summer because? Ans: A plant's leaves are green in
the summer because they contain chlorophyll. Chlorophyll is a natural
pigment that absorbs all wavelengths in the visible spectrum except green.
How many naturally occurring elements exist? Ans: 91
What was Dalton's Atomic theory? (1808) Ans: - Elements are composed of
small particles called Atoms.
- Atoms of a given element are different from atoms of other elements.
-Chemical reactions happen when atoms are rearranged.
- Compounds contain 2 or more elements.
What was J.J. Thomson's experiment, and what did he discover? Ans: Using
a Cathode Ray Tube, he noticed that particles emerged to the cathode disk,
and moved to another, the anode. These particles could be deflected by
electrical fields that would indicate that they would be negatively charged.
They were also deflected by magnetic fields, which showed the particles
carried the charge as the ray was bent. The most important observation was
that the type of cathode used did not matter, as these particles were still
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emitted. Therefore, Thomson deduced that the particles were universal and
were in fact negatively charged components of the atom. (The Electron)
What was Ernest Rutherford's experiment, what did he discover? Ans: Ernest
Rutherford fired Alpha particles (Hydrogen atoms) at a thin sheet of gold
foil. Had Thomson's theory been right about the plum pudding model, then
the atoms should have all passed right through the sheet with no
exceptions. However, a small ratio of these particles were deflected. With
this information, Rutherford figured there was a small dense nucleus in the
atom and that most of the atom was empty space.
What is the difference between Law and Theory? Ans: A law describes - tells
you what happens
A theory explains - tells you why it happens
How big is an atom (H)? Ans: About 0.1 nanometer (0.1 x 10-9m)
Where did the idea of atoms come from? Ans: The Greeks
Atoms Ans: The smallest unit of an element
What is the evidence from Thomson's experiment that all atoms contain
electrons? Ans: The particles are identical regardless of the identity of the
cathode(where they were emitted from).
What is an alpha particle? Ans: Has 2 protons and 2 neutrons. It is the
nucleus of a Helium atom.
Coulomb's Law Ans: Negative and positive charges attract and like charges
repel.
4 Types of Forces Ans: Gravitational, Electromagnetic, Strong Nuclear, Weak
Nuclear
Gravitational Force Ans: Responsible for attraction between objects that
have mass.
Electromagnetic Force Ans: Responsible for attraction/repulsion for objects
that have an electric charge.
Kinetic Energy Ans: The energy associated with motion.
© 2026 All rights reserved
Michigan State University
CEM 141 CEM 141 MSU Exam 1 Questions
and Answers 2026 Latest Update
The statement "If I add cold milk to hot coffee the temperature will
decrease," is a? Ans: Claim, always include an explanation and reasoning to
the claim.
Scientific Model Ans: Models are used to make testable predictions
How much is a picometer? Ans: 0.1 x 10^-12 meters
Atomic Force Microscopy/ Scanning Tunneling Microscopy Ans: Microscopes
that now allows us to view atoms.
Leaves are green in the summer because? Ans: A plant's leaves are green in
the summer because they contain chlorophyll. Chlorophyll is a natural
pigment that absorbs all wavelengths in the visible spectrum except green.
How many naturally occurring elements exist? Ans: 91
What was Dalton's Atomic theory? (1808) Ans: - Elements are composed of
small particles called Atoms.
- Atoms of a given element are different from atoms of other elements.
-Chemical reactions happen when atoms are rearranged.
- Compounds contain 2 or more elements.
What was J.J. Thomson's experiment, and what did he discover? Ans: Using
a Cathode Ray Tube, he noticed that particles emerged to the cathode disk,
and moved to another, the anode. These particles could be deflected by
electrical fields that would indicate that they would be negatively charged.
They were also deflected by magnetic fields, which showed the particles
carried the charge as the ray was bent. The most important observation was
that the type of cathode used did not matter, as these particles were still
© 2026 All rights reserved
, 2 | Page
emitted. Therefore, Thomson deduced that the particles were universal and
were in fact negatively charged components of the atom. (The Electron)
What was Ernest Rutherford's experiment, what did he discover? Ans: Ernest
Rutherford fired Alpha particles (Hydrogen atoms) at a thin sheet of gold
foil. Had Thomson's theory been right about the plum pudding model, then
the atoms should have all passed right through the sheet with no
exceptions. However, a small ratio of these particles were deflected. With
this information, Rutherford figured there was a small dense nucleus in the
atom and that most of the atom was empty space.
What is the difference between Law and Theory? Ans: A law describes - tells
you what happens
A theory explains - tells you why it happens
How big is an atom (H)? Ans: About 0.1 nanometer (0.1 x 10-9m)
Where did the idea of atoms come from? Ans: The Greeks
Atoms Ans: The smallest unit of an element
What is the evidence from Thomson's experiment that all atoms contain
electrons? Ans: The particles are identical regardless of the identity of the
cathode(where they were emitted from).
What is an alpha particle? Ans: Has 2 protons and 2 neutrons. It is the
nucleus of a Helium atom.
Coulomb's Law Ans: Negative and positive charges attract and like charges
repel.
4 Types of Forces Ans: Gravitational, Electromagnetic, Strong Nuclear, Weak
Nuclear
Gravitational Force Ans: Responsible for attraction between objects that
have mass.
Electromagnetic Force Ans: Responsible for attraction/repulsion for objects
that have an electric charge.
Kinetic Energy Ans: The energy associated with motion.
© 2026 All rights reserved
