CEM 141 Exam #1 Question and
answers verified to pass 2025
What is a scientific question? i.e. what can it be answered by? - correct
answer ✔scientific questions can be answered by:
-doing experiments
-making observations
-taking measurements
*must be able to be repeated
ex) what temp. will my coffee be if I add milk to it?
What 3 parts do you need for a scientific explanation? Further explain what
they mean. - correct answer ✔1. Claim: the target of your explanation
2. Evidence: the data or scientific principle you are using to support your
claim; comes from your experiment
3. Reasoning: the connection between your claim and evidence
* all this information develops an explanation or theory
What is a scientific model and what does it help do? - correct answer ✔A
scientific model...
-can be a drawing, graph, diagram, or equation
-help make sense by explaining how something happens and making testable,
quantifiable predictions
What is a scientific theory? - correct answer ✔-best explanation of existing
evidence and data
,-explains how/why
-makes testable predictions
-can be proven false
-can change over time
What is the difference between a law and a theory? - correct answer ✔-a law
describes a phenomenon (answers what?)
-a theory explains the phenomenon (answers why?)
Special relativity (time and space are not absolute but relative to each other)
is an example of a....? - correct answer ✔theory
The force of attraction between masses is proportional to the product of the
masses...is an example of a...? - correct answer ✔law
An atom of hydrogen has one proton is an example of a...? - correct answer
✔fact
If we add reagent X to a reaction it will go faster if an example of a ....? -
correct answer ✔hypothesis
What will happen if we add X to the reaction? is an example of a...? - correct
answer ✔question
What did Feynman write about atoms? - correct answer ✔"all things are
made of atoms-little particles that move around in perpetual motion, attracting
each other when they are a little distance apart, but repelling on being
squeezed into one another."
, Which has atoms in it? Heat, Cells, Air, Gold - correct answer ✔Cells, air,
and gold
Which is biggest? An atom, a molecule, a cell, it depends - correct answer
✔a cell/ it depends
How big is an atom (H)? - correct answer ✔about 0.1 nanometer (0.1x10^-
9m)
*0.1 mm is smallest unit seen by human eye
What two methods provide images at the atomic level? - correct answer ✔-
Atomic force microscopy (AFM)
-Scanning tunneling microscopy (STM)
Where did the original idea of atoms come from? What are some
characteristics of their beliefs? - correct answer ✔-the Greeks: "Atomos": not
to be cut
-based on philosophy; not evidence
-elements; earth, fire, air, and water
-atoms were in constant motion-based on watching the movement of specks
of dust in sunlight--> Brownian motion
-believed shape of atoms played a role in properties-->foreshadowed
molecular structure determining properties
answers verified to pass 2025
What is a scientific question? i.e. what can it be answered by? - correct
answer ✔scientific questions can be answered by:
-doing experiments
-making observations
-taking measurements
*must be able to be repeated
ex) what temp. will my coffee be if I add milk to it?
What 3 parts do you need for a scientific explanation? Further explain what
they mean. - correct answer ✔1. Claim: the target of your explanation
2. Evidence: the data or scientific principle you are using to support your
claim; comes from your experiment
3. Reasoning: the connection between your claim and evidence
* all this information develops an explanation or theory
What is a scientific model and what does it help do? - correct answer ✔A
scientific model...
-can be a drawing, graph, diagram, or equation
-help make sense by explaining how something happens and making testable,
quantifiable predictions
What is a scientific theory? - correct answer ✔-best explanation of existing
evidence and data
,-explains how/why
-makes testable predictions
-can be proven false
-can change over time
What is the difference between a law and a theory? - correct answer ✔-a law
describes a phenomenon (answers what?)
-a theory explains the phenomenon (answers why?)
Special relativity (time and space are not absolute but relative to each other)
is an example of a....? - correct answer ✔theory
The force of attraction between masses is proportional to the product of the
masses...is an example of a...? - correct answer ✔law
An atom of hydrogen has one proton is an example of a...? - correct answer
✔fact
If we add reagent X to a reaction it will go faster if an example of a ....? -
correct answer ✔hypothesis
What will happen if we add X to the reaction? is an example of a...? - correct
answer ✔question
What did Feynman write about atoms? - correct answer ✔"all things are
made of atoms-little particles that move around in perpetual motion, attracting
each other when they are a little distance apart, but repelling on being
squeezed into one another."
, Which has atoms in it? Heat, Cells, Air, Gold - correct answer ✔Cells, air,
and gold
Which is biggest? An atom, a molecule, a cell, it depends - correct answer
✔a cell/ it depends
How big is an atom (H)? - correct answer ✔about 0.1 nanometer (0.1x10^-
9m)
*0.1 mm is smallest unit seen by human eye
What two methods provide images at the atomic level? - correct answer ✔-
Atomic force microscopy (AFM)
-Scanning tunneling microscopy (STM)
Where did the original idea of atoms come from? What are some
characteristics of their beliefs? - correct answer ✔-the Greeks: "Atomos": not
to be cut
-based on philosophy; not evidence
-elements; earth, fire, air, and water
-atoms were in constant motion-based on watching the movement of specks
of dust in sunlight--> Brownian motion
-believed shape of atoms played a role in properties-->foreshadowed
molecular structure determining properties
