Unit 3: Atoms and Elements: Classification Lab
name:_______________________
period: _________________
Part 1
What does it mean to classify a group of objects?
Background: ______________________________________ is the process of grouping things based on their similarities. Chemists use
classification to organize __________________________ into groups so that they are easier to study.
Elements are made up of
______________. We use the ____________________________ to organize the elements based on their atomic properties; the elements are
____________________________ which means their properties have a regular repeating pattern. By using these patterns, we can predict the
properties of unknown elements.
Periodic
Elements
Periodic Table
Procedure:
1. Gather a set of manipulatives from the
center lab table.
2. In your group, plan out how you could
organize them. (this could be the size, color,
shape, mass, or something else!)
3. Place your group’s objects on the lab table
in the same way you would organize them
according to your plan.
4. On the next page, draw your group’s system
of classification. Make sure to include a key
that explains how it is organized!
Extend Yourself
With your lab group, come up with more than one
way to classify your set of objects. In a TAGS
response, answer the following question:
“Is one of the classifications more ‘correct’
than the others? Why?”
Classification
Young
Mendeleev says:
“An organized
student is a
successful
student!”
Atoms
Unit 3: Atoms and Elements: Classification Lab
Look at your objects carefully and list 6 different methods that you could classify them.
Choose one method and separate your groups. Describe why you chose this method.
Extension: Describe how/if you can use more than one classification at the same time.
Draw your organized chart here. USE A RULER!!
Unit 3: Atoms and Elements: Classification Lab
Directions: Open up your lab table notebook to find directions for your tests. In your group, you will complete two
or three tests on the samples at your table. In the boxes below, record your observations and inferences.
Test 1
What will you be testing?
What observations do you expect to make?
What do you expect these observations to tell you? Do you think you will find any patterns?
Observations (at least three):
Inferences In the space below, describe what
patterns or properties that you infer from your
observations. Support your inferences by linking
them to your observations with an arrow.
-
1.
2.
-
3.
-
4.
-
5.
-
Unit 3: Atoms and Elements: Classification Lab
Directions: Open up your lab table notebook to find directions for your tests. In your group, you will complete two
or three tests on the samples at your table. In the boxes below, record your observations and inferences.
Test 2
What will you be testing?
What observations do you expect to make?
What do you expect these observations to tell you? Do you think you will find any patterns?
Observations (at least three):
Inferences In the space below, describe what
patterns or properties that you infer from your
observations. Support your inferences by linking
them to your observations with an arrow.
-
1.
2.
-
3.
-
4.
-
5.
-
Unit 3: Atoms and Elements: Classification Lab
Did you know?
Professional scientists often share data with each other when they are researching similar things.
Directions: In the space below, record the data that other groups report during our discussion. You will use this
information later when you try to classify atoms based on their chemical and physical properties.
Group Number __________
What was tested?
Group Number ____________
What was tested?
What patterns were inferred?
What patterns were inferred?
Group Number ___________
What was tested?
What patterns were inferred?
Group Number __________
What was tested?
What patterns were inferred?
Unit 3: Atoms and Elements: Classification Lab
Summarize: In the space below, summarize the patterns for chemical and physical properties our class observed.
This can be done in a table, in bullets or in paragraph form.
Chemical Properties:
Physical Properties:
Name: _____________________
Period: ________
Unit 3: Atoms and Elements: Classification Lab
1
8
The Mystery Element Identification Game!
Which element is which? Use your periodic table, lab data and patterns of chemical and physical
properties of atomic families to fill in this blank periodic table. Include the letter of the unknown
element, the element’s name and how you identified the element from the clues given.
1
Be careful… they won’t all be present or in order.
2
2
3
3
4
5
6
7
Unit 3: Atoms and Elements: Classification Lab
Chemicals in the stockroom:
CaCl
LiCl
SrCl
KCl
HOOH
K2CrO4, K2Cr2O7
KMnO4
Al2(SO4)3
NaAcetate
Bleach
CuCl2
Na2SiO3
NaHCO3
Vinegar
Si
Na
Mg
Sucrose
Borax
Phosphorus (from matches)
Al (foil)
Objectives
SW classify a group of
objects (chemicals) by
their physical and
chemical properties
Activity
- intro
classification
- atomic properties
classification
practice
Tests:
pH of solids and solutions
Conductivity of solids and solutions
Solubility
Reading/video on noble gasses?
Reading/video on halogens?
Video/demo of alkali metals and water
Density
Shine and ductility
flammability
Assessment
Classify and order
unknown samples /
prompts
Differentiate/Remediate
Unit 3: Atoms and Elements: Classification Lab
Reactivity with water (1)
Li, Si, Al
We know that we’ve observed a reaction when bubbles, heat, sparks or chemical properties change when
two substances come together. One group on the periodic table reacts explosively with water when under the right
conditions.
Example: Heat and bubbles are formed when some groups on the periodic table come into contact with water.
You will be given samples of Aluminum, Silicon, and Lithium and sugar. One at a time, place a small piece of the
samples into water and record what happens.
Unit 3: Atoms and Elements: Classification Lab
Testing for acidity Using pH strips (1)
NaOH, HCl, vinegar, H2CO3, borax solution
Acids and bases can discolor clothing, burn skin and lungs, and corrode metals. You must
use EXTREME caution when working with these chemicals!!!!!!!
There are substances which have the property of changing their color when
they come in contact with an acidic or basic environment. These substances
are called pH indicators. We can use special papers which have been
soaked with indicators to tell the pH of a solution. These papers change color
when they are immersed in acidic or basic liquids. This is the case of the
well-known litmus paper.
Using Litmus paper. To use litmus paper, simply touch the paper to the
sample you want to test. Try it with your solid sample first, then test the
liquids. Remove it immediately and compare the color of the paper to the
provided scale. A pH reading from 0-7 means that your sample is acidic. A
pH reading of 7-14 means that your sample is basic.
Procedure:
1. Touch the test strip to each of your solid samples. Observe any color change you notice on the test strip and
compare the color to the key on the package.
2. Record your observations.
3. Pour water in each of your solid samples.
4. Dip a pH strip in a liquid sample. Observe any color change you notice on the test strip and compare the color
to the key on the package.
5. Repeat step 4 with a new pH strip for all of your samples.
6. Record your observations.
Unit 3: Atoms and Elements: Classification Lab
Testing for solubility (2)
NaCl, CaCl2, Si, Al, AlCl3, sugar
In a solubility test, we are observing how well our substance mixes into the solvent (the liquid). We
consider a substance soluble if the solid crystals disappear when they are mixed in.
NOT Soluble
Procedure:
1)
2)
3)
4)
5)
6)
Soluble
Perform the solubility test only AFTER you have tested the conductivity of your DRY samples!
Note the amount of solid in each of your beakers.
Have a team member get a sample of water from the sink
Pour water into each beaker until the beaker is half full, and then stir it.
Compare the amount of solid at the bottom of your beaker to your starting amount.
Record your observations.
Unit 3: Atoms and Elements: Classification Lab
Testing for conductivity using a digital probe (2)
NaCl, CaCl2, sugar, AlCl3
Electrical Conductivity refers to a substance’s ability to transfer electrons. Our digital probes can tell us a
solution’s conductivity on a scale of 1-10. A low reading (1-4) means that electrons cannot flow between particles
easily. A high reading (7-10) means that electrons can move with ease.
Procedure:
1) For this test, we will look at the conductivity of crystal samples before studying the conductivity of
solutions.
2) To use our probes, press the button on the side of the probe and you should see a red light next to the ON
text. You must hold the button down for the probe to take measurements.
3) Dip the metal ends into the chemical you want to test and watch the scale on the front of the meter. If the
meter doesn’t light up, it means that the sample is NOT conductive.
4) Record the conductivity of each sample in your observations.
5) Once you’ve measured the conductivity of each dry sample, complete the solubility test.
6) Once you’ve completed the solubility test, repeat steps 2-5 for your solutions.
Unit 3: Atoms and Elements: Classification Lab
Reactivity with Oxygen (3)
H2, cellulose, N2, Mg
Density
Mg, Al, Si
Noble Gases (3)
http://noblegases2.webs.com/argon.htm
Maleability
Mg, Al, C (graphite)
Physical appearance (3)
Mg, Al, S, C, B, air?
Unit 3: Atoms and Elements: Classification Lab
Argon,
Hi people, as you know I’m
Argon, or the Jealous
one, that’s what the rest of the no good, creditstealing family calls me. I mean seriously I’m in
NEON lights and HELIUM balloons but you don’t
hear it being named after me. As you can probably
tell I get angry real easy and I hold grudges for a
long time, (Argon has a boiling point of, 185.85°C or -302.53°F).
I also get upset really easily (Argon has a low
melting point of, -189.35°C or -308.83°F). I
have a lot of the same characteristics as the rest
of my family, for example I am (odorless and
colorless). I was born (discovered) in 1894 in
Scotland. Sir William Ramsay, a Scottish chemist, and Lord Rayleigh, an English chemist, discovered
me. I was the first of the Noble Gas family to be discovery, (Ya that’s right family I'm
number one, what you going to do now). My name, Argon, comes from the Greek word "argos"
meaning "inactive," (Argon's symbol is Ar).
Like the rest of the family I can get really selfish ( Argon doesn't share ANY of it's valence
electrons). If you're every looking for me you will find me in Earth's Atmosphere. You can also find
me in area were there is arc weilding going on. My favorite numbers 18 (atomic # is 18). Even
though I am one of the most unactive elements in the whole periodic table I don't weigh all that
much (Argon weighs 39.948 amu).
Unit 3: Atoms and Elements: Classification Lab
HI, I am Xenon or the angry one. I was discovered by William Ramsay in 1898 (William
Ramsay discovered Xenon in 1898), I know don't say it I'm old. Please don't call me by
my greek name Xenos it means "strange" (The greeks called Xenon Xenos wich means
Whats the deal with us noble gases being inert I mean I have some
buddies Flourine and Oxygen (When they discovered Xenon they said it was inert
but in the 1960's they figured out it wasn't inert it rarely combines with other
elements like fluorine and oxygen).
"strange").
Sorry, I get mad very easily (Xenons boiling point is -108.12 degrees celsius). I
get really mad when radon wins hide-and-seek.... well, radon wins all the
time,"hmff"!(Xenon is found in the atmosphere 80 parts per billion!). I also get
very exited ( Xenon produces a brilliant white light whenit is excited
electrically). I am always found next to last, you know what I mean your like
so close to winning and then you lose.
I Like to hang by metiorites and minerals,(you might find xenon in meteorites
and minerals) but my family always remembers at the last second when they
are about to forget. Most of all I think I have super powers, you see I can't
combust in other words catch on fire (Xenon can't catch on fire). That’s all I
have to say about me. Stop looking at me!