Name:_________________________________
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Lab Report Prewriting Assignment
Title: Properties of Compounds
Introduction
Why did we do this lab? (What did we what to
show or prove?)
The purpose of this lab was to determine the
melting points and conductivity of ionic and
covalent compounds.
What technique was used to perform the
experiment?
The conductivity was determined using a
conductivity apparatus. The melting point
was determined using a Bunsen burner. The
type of bond was determined using a periodic
table.
What do we need to know about in order to
understand this lab?
To understand this lab we need to know
about ionic and covalent bonds, electrolytes,
melting point and the organization of the
periodic table according to element classes.
Hypothesis
What do you think will happen?
I think the covalent compounds will have
similar conductivity and melting points. I
also believe the ionic compounds will have
similar conductivity and melting points,
though they will be different than the
covalent compounds.
Procedure
Stepwise directions (Past tense with no personal
pronouns)
At station 1 there were eight Dixie cups, each
containing a solution of one of the
compounds to be tested. Each solution was
tested for conductivity by placing the probe
of the conductivity apparatus into the
solution. If the solution was conductive the
light bulb lit up. If the solution was not
conductive, the light bulb did not light up.
The results for each test were recorded into
data table 1. After each test, the probe was
cleaned by immersing it in a beaker of clean
water.
At station 2 a sample of each compound was
placed in a separate test tube. The test tube
was then held in the flame of a lit Bunsen
burner. If the substance melted, the melting
point was considered to be low. If the
substance did not melt, the melting point was
considered to be high. The data was recorded
in data table 2.
At station 3 each substance was identified as
either ionic or covalent by determining what
types of elements make up the compound. If
the compound contains a metal, the
compound was identified as ionic. If the
compound was only made up of nonmetals it
was identified as covalent. The results were
recorded in data table 3.
Results
Titles and numbers of tables and figures to be
included in your report
Data table 1: Properties of Compounds Lab
Data Summary
Summarize overall results in sentence form
In data table 1, the results from the melting
point experiment, electrolyte lab and the
bond identification station were recorded.
Conclusion
Describe the data collected
C6H12O6, H2O, C12H22O11 and C6H10O5 were
all identified as covalent compounds. Each
had a low melting point and did not conduct
electricity. NaOH, NaCl, NaHCO3 and CaCl2
were all identified as ionic compounds. Each
had a high melting point and did conduct
electricity.
Explain what the data tells you (Does it support
or refute your hypothesis)
All of the compounds identified as covalent
compounds had low melting points and did
not conduct electricity when dissolved in
water. I would predict most covalent
compounds will share these same properties.
All the compounds identified as ionic
compounds had high melting points and did
conduct electricity when dissolved in water. I
would predict most ionic compounds will
share these properties.
What, if anything, went wrong in this
experiment? How might you improve this
experiment?
The probe for the conductivity apparatus
must be cleaned between each test. Using
more compounds would give us more
accurate data.