Chemical Properties Lab Output
DATE
Chemical Properties Input
DATE
18 Nov 13/DCM
Content Purpose: Identify and explain the chemical
properties of matter.
Question: Can a chemical reaction help identify an unknown
substance?
Examples of Chemical Properties:
Activity 5.1 Journaling:
Variables:
Dep – (what’s being measured?) – chemical rxtn to the unknown
liquids.
Ind – (what’s being changed) – baking soda
Control – what stays the same or is not manipulated. There is no
control in this experiment.
Observations:
Period 1
A – odor is like vinegar. Clear. Water-like viscosity. Feels like
grease or residue.
B – no odor. Clear. Water-like viscosity. Did not leave a residue
after it dried.
Period 7
Liquid A – smells strong like vinegar. Clear. Water-like viscosity.
Liquid B – looks like water. No odor. Clear. Water-like viscosity.
Prior knowledge from 5th grade lab says that if liquid A is vinegar it
should bubble when mixed with baking soda (NaHCO3).
Bigbrainscience.com stated that vinegar is an acid and reacts with
baking soda which is a base. (we know that a reaction should result
in color change, bubbling, heat loss or gain, or precipitate).
Yahoo.com stated baking soda and water (possibly liquid B) will
release CO2 gas. Another person said that baking soda and water
will just make the baking soda wet.
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ABILITY TO RUST
FLAMMABILITY
REACTION WITH ACIDS
SPOILING
COMBUSTABILITY
Chemical Change: A new substance is formed (reaction)
Circle the chemical change?
boiling water
tearing clothes
tarnishing silver
lighting a match
chewing food
breaking a stick
a rusting nail
burning gas in a stove
melting ice cream
sawing wood
oxidizing food for energy
stretching a rubber band
spoiled potato salad
baking a cake
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Flip Chart 1 Cont…
Flip Chart 1:
Procedures:
Hypothesis:
If baking soda is mixed with liquid A & B then the identity of liquid A
will be vinegar and liquid B will be water and can be determined
because of the indication of a chemical reaction.
If baking soda is added to the unknown substances then the identity
of the substances can be determined because of their unique
chemical reactions to the baking soda.
If baking soda is added to liquid A and liquid B then liquid A
will be proven to be vinegar and liquid B will be proven to be
water because of their distinct chemical reactions to baking soda.
Materials:
Test tube
Pipettes
3 beakers
Liquid A
Liquid B
NaHCO3
Test tube rack
Metal spatula
Tape & pen
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2
2
100 ml
60 ml
60 ml
5 ml
1
1
enough to label all items
1. Safety: there are no dangers in this lab, however goggles
and apron are recommended and use caution working with
glass.
2. Label all equipment properly.
3. Take small amount of NaHCO3 with spatula and put in test
tubes
4. Take pipette and add several drops of liquid A into test tube
A. Record results.
5. Repeat step 4 for liquid B.
6. Clean up
Observations:
Liquid A –
Liquid B –
Flip Chart 2:
Draw what you see for each trial:
Liquid a
Liquid B
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Flip Chart 3:
Conclusion:
If baking soda is added to liquid A and liquid B then liquid A will be
proven to be vinegar and liquid B will be proven to be water because
of their distinct chemical reactions to baking soda.
Purpose of the lab
The purpose of the lab was to determine if a chemical reaction can
help identify an unknown substance.
Relationship between variables
The ind variable (baking soda) when mixed with the dep variable
(liquid A) caused gas to be released in the form of fizzing bubbles.
When baking soda was mixed with the dep variable (liquid B) there
was little to no indication of a chemical reaction.
The ind var (baking soda) would affect the dependent variables
(liquid A & B) by causing a chemical reaction with liquid A
(fizz/bubble) and causing little to no chemical reaction with liquid B.
Hypothesis Explanation
Period 1
The hypothesis stated, “If baking soda is added to liquid A and liquid
B then liquid A will be proven to be vinegar and liquid B will be
proven to be water because of their distinct chemical reactions to
baking soda.” The hypothesis was proven correct because when
liquid A was added to baking soda it fizzed and bubbled up which is
an indication of chemical reaction which proved that liquid A was
vinegar. Liquid B was proven to be water because the baking soda
did not react and sank to the bottom.
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Flip Chart 3 Cont…
Period 7:
The hypothesis stated “If baking soda is added to liquid A and liquid
B then liquid A will be proven to be vinegar and liquid B will be
proven to be water because of their distinct chemical reactions to
baking soda.” The hypothesis was supported in the experiment
because each liquid had distinct reactions that proved what they were
based on research and past knowledge.
Explanation of results
Period 1:
When the liquid A was added to baking soda it fizzed up and
bubbled in a distinct chemical reaction where gas was released
proving it was vinegar based on research and background
knowledge.
When liquid B was added to baking soda there was no chemical
reaction (it sank to the bottom) proving is was water based on
research and background knowledge.
Period 7:
Liquid A was found to be vinegar because when it was mixed with
baking soda the solution fizzed and bubbled in a chemical reaction.
Liquid B was found to be water because there was a subtle chemical
reaction; the baking soda sank to the bottom.
Procedural errors
There were no procedural errors in this experiment. (list any that
may have happened at your personal table. Remember to explain
how this may have affected the lab.)
Further investigation
Thermometer could be used to determine if heat was absorbed or
released. This would further indicate a chemical reaction had
occurred.
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It might help to use larger samples so the reactions would be
obvious. This would aid in the observations.
Real-world application
You’re on your own  Think of how the purpose of the lab and its
results could be used in the big wide world
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