CEM 141
CEM 141 MSU Exam 1 Study Questions with
Correct Answers Graded A+ 2026
The statement "If I add cold milk to hot coffee the temperature will decrease," is
a? -Correct Answer ✔-Claim, always include an explanation and reasoning to the
claim.
Scientific Model -Correct Answer ✔-Models are used to make testable predictions
How much is a picometer? -Correct Answer ✔-0.1 x 10^-12 meters
Atomic Force Microscopy/ Scanning Tunneling Microscopy -Correct Answer ✔-
Microscopes that now allows us to view atoms.
Leaves are green in the summer because? -Correct Answer ✔-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? -Correct Answer ✔-91
What was Dalton's Atomic theory? (1808) -Correct Answer ✔-- 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? -Correct Answer
✔-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 emitted. Therefore,
CEM 141
, CEM 141
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? -Correct Answer
✔-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? -Correct Answer ✔-A law
describes - tells you what happens
A theory explains - tells you why it happens
How big is an atom (H)? -Correct Answer ✔-About 0.1 nanometer (0.1 x 10-9m)
Which is biggest? Atom, Molecule, Cell, or it depends? -Correct Answer ✔-
Where did the idea of atoms come from? -Correct Answer ✔-The Greeks
Atoms -Correct Answer ✔-The smallest unit of an element
What is the evidence from Thomson's experiment that all atoms contain
electrons? -Correct Answer ✔-The particles are identical regardless of the identity
of the cathode(where they were emitted from).
What is an alpha particle? -Correct Answer ✔-Has 2 protons and 2 neutrons. It is
the nucleus of a Helium atom.
Coulomb's Law -Correct Answer ✔-Negative and positive charges attract and like
charges repel.
CEM 141
CEM 141 MSU Exam 1 Study Questions with
Correct Answers Graded A+ 2026
The statement "If I add cold milk to hot coffee the temperature will decrease," is
a? -Correct Answer ✔-Claim, always include an explanation and reasoning to the
claim.
Scientific Model -Correct Answer ✔-Models are used to make testable predictions
How much is a picometer? -Correct Answer ✔-0.1 x 10^-12 meters
Atomic Force Microscopy/ Scanning Tunneling Microscopy -Correct Answer ✔-
Microscopes that now allows us to view atoms.
Leaves are green in the summer because? -Correct Answer ✔-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? -Correct Answer ✔-91
What was Dalton's Atomic theory? (1808) -Correct Answer ✔-- 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? -Correct Answer
✔-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 emitted. Therefore,
CEM 141
, CEM 141
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? -Correct Answer
✔-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? -Correct Answer ✔-A law
describes - tells you what happens
A theory explains - tells you why it happens
How big is an atom (H)? -Correct Answer ✔-About 0.1 nanometer (0.1 x 10-9m)
Which is biggest? Atom, Molecule, Cell, or it depends? -Correct Answer ✔-
Where did the idea of atoms come from? -Correct Answer ✔-The Greeks
Atoms -Correct Answer ✔-The smallest unit of an element
What is the evidence from Thomson's experiment that all atoms contain
electrons? -Correct Answer ✔-The particles are identical regardless of the identity
of the cathode(where they were emitted from).
What is an alpha particle? -Correct Answer ✔-Has 2 protons and 2 neutrons. It is
the nucleus of a Helium atom.
Coulomb's Law -Correct Answer ✔-Negative and positive charges attract and like
charges repel.
CEM 141
