Expert answer:properties of substances

Answer & Explanation:Properties of Substance Lab.docx
properties_of_substance_lab.docx

Unformatted Attachment Preview

Properties of Substances Lab Graded Assignment
Question:
What changes occur when chemicals are mixed, and which changes signal that a physical or chemical
reaction has occurred?
Hypothesize:
Look at the substances in the materials list. Make an educated guess about what physical or chemical
changes might occur when some of them are mixed. Write your hypothesis as an if-then statement
such as, “If I mix water and chalk powder, then the chalk will dissolve but no chemical change will take
place” (You must make 3 educated guesses of what you believe will happen or what you will
observe…3 points)
Procedure:
1. Using the scoopula, fill well 1A of the microplate approximately one-fourth of the way
with chalk. Using a pipette, slowly add 25 drops of distilled water to the chalk. Stir with a
toothpick. Record your results in the “Observations Immediately After Mixing” chart.
2. If there is no Reaction, write NR.
3. Use the scoopula to put the chalk and other solids into the microplate wells.
4. Add 25 drops of citric acid solution. Use a clean pipette to add the citric acid solution. Stir
with a clean toothpick. Record results.
5. Repeat with 25 drops of vegetable oil and then .1M NaOH. Record all results
6. Allow enough time for the liquids to evaporate. After the liquids evaporate, study each
well with your hand lens.
7. In the data table “Observations of Mixtures After Evaporation”, record your observations
of the dry samples that are left behind. Consider such factors as change in crystal
appearance.
Data Table 1
1
Chalk
A
Distilled
water
B
3M
Citric Acid
C
Vegetable
Oil
D
.1M
NaOH
Data Table 2
1
Chalk
A
Distilled
water
B
3M
Citric Acid
C
Vegetable
Oil
D
.1M
NaOH
Observations of Mixtures Immediately After Mixing (7 points)
2
NaCl
3
KCl
4
Baking Soda
5
Sugar
6
Vinegar
Observations of Mixtures Immediately After Evaporation (7 Points)
2
NaCl
3
KCl
4
Baking Soda
5
Sugar
6
Vinegar
Analyze
Answer each of the following thoroughly.
1.
Go back to your observations tables and underline all observed changes that you noted
that you think were physical changes.(3 points)
2.
Go back to your observations tables and either circle or highlight all observed changes
that you think were chemical changes.(3 points)
3.
In considering your observations of the mixtures, look for similar patterns of behavior.
Which pairs of substances produced almost the same results in each mixture that they
were found in? (3 points)
4.
Make a general statement about whether your hypotheses were validated or rejected. Must
your hypotheses be correct for this to be a successful laboratory? (4 points)
…
Purchase answer to see full
attachment

How it works

1. Paste your instructions in the instructions box. You can also attach an instructions file
2. Select the writer category, deadline, education level and review the instructions 
3. Make a payment for the order to be assignment to a writer
4.  Download the paper after the writer uploads it 

Will the writer plagiarize my essay?

You will get a plagiarism-free paper and you can get an originality report upon request.

Is this service safe?

All the personal information is confidential and we have 100% safe payment methods. We also guarantee good grades