Chemistry Question

Science | Lab Report
Lab Report
[Use this document as a template for writing your lab report. Descriptions of what to include and examples of each
section have been provided. Before submitting this document to your teacher, delete all the text in brackets,
including this text.]
Title
[This is the title of the lab lesson.
Example: Effect of Soap on Surface Tension of Water]
Type your title here.
Introduction
[This section describes the principles and concepts related to the experiment. It is used to help the person reading
your report to understand the information that serves as foundation for the experiment. It also includes a brief
statement about the purpose of the lab.
Example: Surface tension is the attractive force exerted upon the surface molecules of a liquid by the molecules
beneath. Water has a high surface tension because there are strong attractive forces between water molecules.
Adding surfactants, like soap, can reduce the surface tension of a liquid. The purpose of the experiment was to
determine the effect of soap on the surface tension of water.]
Type your introduction here.
Experimental Methods
[This section should be written in paragraph form and describe how the experiment was conducted, including a
description of controls and how the measurements were taken.
Example: The surface tension of water was tested by counting the number of drops that could fit on the head of a
penny before it spilled over. Both samples of water were left at room temperature for several hours before use.
Approximately 1 mL of soap was added to one sample of water. The same penny was used for both tests, and it
was rinsed and dried thoroughly between tests. Three trials were conducted for each test.]
Type your experimental methods here.
Data and Observations
[This section should include descriptions of results and organized data tables and/or graphs, depending on the
experiment. It is important that the data be easy to read and interpret and include appropriate labels and
descriptions.
Example:
Table 1. Average Number of Drops Added to Head of Penny for Three Trials.
Sample
Average number of drops
water
50
water and soap
10
© Stride, Inc. All rights reserved. No reproduction without written consent of Stride, Inc.
Page 1 of 2
Science | Lab Report
]
Type your data and observations here.
Discussion and Conclusions
[Use the questions in your lab lesson to complete this section.
Example:
Soap reduced the surface tension of water because only 10 drops of water and soap mixture were added to the
penny before the liquid spilled over, compared to 50 drops of water without soap. Sources of error include
variations in the volume added with each drop, the time between drops, and the surface of the penny being
cleaned as the water/soap mixture is added in each trial. The experiment could be improved by observing other
indications of surface tension, including measuring the contact angle.]
Type your discussion and conclusions here.
© Stride, Inc. All rights reserved. No reproduction without written consent of Stride, Inc.
Page 2 of 2
Science | Graded Assignment Answer Key | Lab Report Rubric
Graded Assignment Answer Key
Lab Report Rubric
Grades are based on quality and timeliness. Responses should be well written (use a spell-checker) and should
clearly address all parts of the experiment. Use the rubric to maximize your grade on your lab report.
Criterion/prompt
Exemplary (5 points)
Proficient (3-4 points)
Emerging (1-2
points)
Not evident (0
points)
Introduction
Includes a clear
description of the
principles and concepts
related to the experiment.
Includes a partial
description of the
principles and
concepts related to
the experiment.
Includes a vague
description of the
principles and
concepts related to
the experiment.
Some of the
descriptions might
be incorrect.
Missing an
Introduction
section.
Experimental
methods
Includes a clear
description of how the
experiment was
conducted. When
applicable, describes the
controls used in the
experiment.
Includes a partial
description of how
the experiment was
conducted.
Includes a vague
description of how
the experiment
was conducted.
Missing an
Experimental
methods
section.
Data and
observations
Provides data and
observations that are easy
to read and interpret. If
data tables and/or graphs
are created as a part of
the experiment, they are
appropriately labeled.
Provides some data
and observations, but
some information is
missing. Data tables
and/or graphs
provided may be
lacking labels.
Provides little data
or observations.
Missing a Data
and
observations
section.
Discussion and
conclusion
Where applicable,
answers questions by
making evidence-based
claims about the results of
the experiment, cites data
or observations, and
discusses possible
sources of error.
Where applicable,
answers some
questions about the
results of the
experiment, cites
some data or
observations, and
discusses possible
sources of error.
Where applicable,
answers few
questions about
the results of the
experiment, cites
little data or
observations, and
does not discuss
sources of error.
Missing a
Discussion and
conclusion
section.
© Stride, Inc. All rights reserved. No reproduction without written consent of Stride, Inc.
Page 1 of 1
Modeling periodic trends
For this lab, you will need to gather these materials:
• Scissors
• Tape or clay
• Paper
• Straws, cardboard, or spaghetti noodles
• Metric ruler
Creating a Scale: First Ionization Energy (eV)
1. Measure the length of a straw (or spaghetti noodle or cardboard, depending on
the materials that you are using).
2. Use the straw length and maximum ionization energy to create a scale for your
model.
For example, the maximum ionization energy in the chart is 24.587 eV. If the straw that
represents the maximum ionization has a length of 20.0 cm, then the straw scale is:
20.0 cm24.587 eV=0.813 cm/eV20.0 cm24.587 eV=0.813 cm/eV
This means that each eV of ionization energy will be represented by 0.813 cm of straw
on the chart. The scale you create will be used to determine the lengths of the other
straws. You may use any length of straw for your scale.
Ionization Energy (eV)
Procedure Part 2 – Create Your Model
1. Sketch this section of the periodic table on a piece of paper.
2. Place a small amount of clay or tape on each element’s square.
3. Determine the length of the straw (or spaghetti noodle or cardboard) for each
ionization energy in the table using the scale from part 1.
For example, use the scale of 0.81 cm/eV to find the length of the straw for hydrogen:
0.813 cm/eV × 13.598 eV = 11.1 cm0.813 cm/eV × 13.598 eV = 1
1.1 cm
4. Cut the straws to scale for each element’s ionization energy.
5. Stick each straw (or spaghetti noodle or cardboard) into the clay or tape on the
paper.
Writing Your Lab Report
Use the Lab Report document as a template. Use the descriptions and examples of each part of
the lab report to help you write your lab report.
Answer these questions in the introduction of your Lab Report:
1. Why are periodic trends useful?
2. What are some examples of periodic trends?
3. What is ionization energy?
4. What was the purpose of creating your three-dimensional model?
Explain how you made your model in the experimental methods section of your Lab Report.
Include a chart that shows the heights of straws used and a picture of sketch of your model in the
data and observations section of your Lab Report.
Answer these questions in the discussion and conclusion of your Lab Report:
1. How does your model represent ionization energy?
2. What happens to the ionization energy of elements as you move from left to right across a
period? Explain the trend.
3. What happens to the ionization energy of elements as you move down a group? Explain
the trend.
4. In reactions between metals and nonmetals, metals tend to form cations while nonmetals
tend to form anions. How does your model show this trend?
Be sure to look at the lab report rubric to see how you will be graded.
Chromatography 1
The Image Analyzer has two image sets with results from two paper chromatography
tests.
Image Set 1: Alcohol Start and Alcohol End show before and after images of ink exposed
to alcohol.
Image Set 2: Oil Start and Oil End show before and after images of ink exposed to oil.
Use the images to measure the distance traveled by several components within each ink
sample. Start by exploring each image. If the ink separated as it traveled through the
paper, mark the place where each color stopped with the drawing tool.
Then, zoom out and measure the distance from the start line to the place where the
color stopped with the measuring tool. Record your observations.
millimeters
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
5
10
15
20
25
30
35
40
45
50
55
60
65
70
Now that you have observed how paper chromatography can be used to identify an unknown, it’s
time to plan and conduct your own paper chromatography experiment.
Note that you should only use the materials suggested to complete your experiment, which
include:
• Coffee filters
• Water
• Water-soluble markers
• Scissors
• Pencil
• Cups
• Tape or clip
lan Your Investigation
Plan an investigation to test one of the following questions:
1. Which color of marker contains the most components?
o Be sure to use the same brand of marker for each color tested.
2. Which brand of marker contains the most components?
o Be sure to use the same color of marker for each brand tested.
General Experimental Procedure:
1. Cut the coffee filter into a large rectangular piece to make it easier to work with.
2. Draw the starting line in pencil about 2 cm above the bottom of the coffee filter.
3. Use the markers to make small dots (approximately 2-3 mm in diameter) along the
pencil line. Leave a space of approximately 1 cm between each dot.
4. Fill your glass so that the water line reaches less than 1 cm from the bottom of
the coffee filter. If your ink dots start in the water, they will bleed into the glass
and you will need to restart the experiment.
5. You may need to tape or clip the top of the coffee filter to a pencil on top of the
glass to hold it in place.
6. Remove the filter from the water before the ink reaches the top edge.
Use the Lab Report document as a template. Use the descriptions and examples of each part to
help you write your Lab Report. Your Lab Report should focus on the results of the experiment
that you conducted, not on the results of the experiment provided with the Image Analyzer.
Answer these questions in the introduction of your Lab Report:
1. What is the principle behind the technique of paper chromatography?
2. What are some uses of paper chromatography?
3. What was the purpose of your experiment?
Answer these questions in the discussion and conclusion of your Lab Report:
1. What does your data tell you about the markers tested?
2. What did you use for controls in your experiment?
3. What are some sources of error in your experiment?
4. How could you modify your experiment?
Be sure to look at the Lab Report Rubric to see how you will be graded.
Page 6 of 6