Name:
Date:
Period:s
This week we will study the properties of ionic and covalent compounds.
CLASS
MONDAY (2/20)
SLCS- no math/chemistry
WEDNESDAY (2/22)
SLCS- no math/chemistry
Homework
Activities
NO SCHOOL
TUESDAY (2/21)
Make sure packet 18 is
completed.
DO ALEKS
ALEKS
THURSDAY (2/23)
FRIDAY (2/24)
We’ll be hearing a talk
from Wildcoast about the
water pollution in the
Tijuana River Estuary. We
will also be visiting the
estuary.
Presentation #2
DO ALEKS
Finish ionic compounds
webquest
Properties of Ionic
Compounds
Write a reflection on ionic
compounds – due
Thursday
http://auden.webster.edu/~scottsus/characteristics.htm
Tutorial on covalent bonding: http://www.youtube.com/watch?v=-Eh_0Dseg3E&feature=related (type in “Chemistry Tutorial 6.01a: How Covalent Bonds Form”)
Ionic and covalent bonding animation: http://www.youtube.com/watch?v=QqjcCvzWwww&NR=1 (type in “ionic and covalent bonding animation)
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Properties of Ionic Compounds Webquest
You’ve recently learned how and why ionic compounds form. Let’s review!
Part 1: Reaction of Sodium with Chloride
Visit this website. http://tinyurl.com/LoveThemIons
Go down to the ionic bonding section and read about it. Then click on the link for “The reaction of sodium with chloride”
and answer the questions below.
1.) In ionic bonding, _____________ are completely transferred from __________________________. When atoms lose
or gain negatively charged electrons, the reacting atoms form __________. These oppositely charged ions are then
attracted to each other and form _________________ compounds.
2.) Click on “The reaction of sodium with chloride.” What happens when you drop the sodium into the chlorine?
3.) Click on “magnify the reaction.” What happens to the sodium atom? Why does the sodium atom’s size change?
4.) What happens to the chlorine atom? Why does the chlorine atom’s size change?
5.) Why does the sodium atom and chlorine atom bond together?
6.) Click on “what compound is formed?” What happens when sodium and chlorine bond together?
Part 2: Ionic Bonding
Go to the following website: http://tinyurl.com/ionictutorial
Read the text on screen and answer the questions that follow
1. What does the typical definition of ionic bonding involve?
2. Click on the right arrow. Follow the directions on the screen. What happens when you move the negative charge
close to the other negative charge?
3. Click on the right arrow. Follow the directions on the screen. What happens when you move the opposite charges
close to each other?
4. Click on the right arrow to screen 5. What do like charges do? What do opposite charges do?
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5. Click on the right arrow. What do atoms that form positive ions tend to do?
6. What usually forms the positive ion?
7. Where can these atoms be found on the periodic table?
8. Click on the right arrow. What do atoms that form negative ions tend to do?
9. What type of atom usually forms the negative ion?
10. Where are these atoms found on the periodic table?
11. Click on the right arrow. What two atoms tend to form an ionic bond?
12. Click on the right arrow and read the following screens. Continue to screen 10.
13. Why are chlorine atoms able to take one electron from the sodium atom?
14. What happens when the sodium atom loses an electron?
15. What happens when the chlorine atom gains an electron? What is it then called?
16. Click on the right arrow. Since the two ions now have opposite charges, what will happen?
17. Click on the right arrow. What is an ionic bond?
18. Click on the right arrow and read the following screens. Continue to screen 18.
19. When other ion pairs are attracted, what is built?
20. Click on the right arrow and read the following screens. Continue to screen 21. Click “Count Na+ Ions” and “Count
Cl- Ions.” What is the ratio of sodium ions to chloride ions?
21. Click on the right arrow. Since the ratio of Na+ to Cl- is 1 to 1, what is the formula?
22. Click on the right arrow. What does the formula tell us?
23. Click on the right arrow. The crystal shown is formed between calcium ions and fluoride ions. In the boxes on the
screen, enter the number of each type of ion present. Check your answers.
24. What is the ratio of calcium to fluoride ions? What does this reduce to? What is the ionic formula?
25. Click on the right arrow. Continue to screen 27.
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Part 3: Ionic Compound Formulas
Go to the following website: http://tinyurl.com/HeyTherePig
On the screen you see scale with a positive and negative side. At the top of the screen, it asks for the formula for a given
compound. On the left, you see ions provided. Click on the “instructions” button. Drag the positive and negative ions to
the scale. You must add enough positive and negative ions to get the formula to balance at neutral. Write the name,
ions, and final balanced formula below. Click on the “new compound” button and repeat this for 4 more compounds.
1. Formula name: __________________________________ Ions: __________ & _________
Balanced formula: _____________
2. Formula name: __________________________________ Ions: __________ & _________
Balanced formula: _____________
3. Formula name: __________________________________ Ions: __________ & _________
Balanced formula: _____________
4. Formula name: __________________________________ Ions: __________ & _________
Balanced formula: _____________
5. Formula name: __________________________________ Ions: __________ & _________
Balanced formula: _____________
Part 4: Writing Ionic Formulas
Go to the following website: http://tinyurl.com/HaveSomeCheese
From the drop-down boxes, select a cation and an anion.
Write these below.
Assign integer (whole number) subscripts to balance the
compound formed by these ions.
Click on the “Total” button to check to see that the net
charge is zero. If it is not, adjust the subscripts.
Repeat this for 5 more combinations.
Cation = positive ion
anion = negative ion
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1. Cation:
_________
Anion: _________
4. Cation:
_________
Anion: _________
Ionic charges: ________
_________
Ionic charges: ________
_________
Subscript:
_________
Subscript:
_________
_________
_________
Formula: _____________________
Formula: _____________________
2. Cation:
5. Cation:
_________
Anion: _________
_________
Anion: _________
Ionic charges: ________
_________
Ionic charges: ________
_________
Subscript:
_________
Subscript:
_________
_________
_________
Formula: _____________________
Formula: _____________________
3. Cation:
6. Cation:
_________
Anion: _________
_________
Anion: _________
Ionic charges: ________
_________
Ionic charges: ________
_________
Subscript:
_________
Subscript:
_________
_________
Formula: _____________________
_________
Formula: _____________________
Part 5: Compound Formula Exercise
Go to the following website: http://tinyurl.com/ThatsALowPrice
On the screen, you will see three lines above yellow boxes with ions, and possibly numbers and parentheses. Your task is
to arrange the yellow boxes between the lines to make correct ionic formulas. Remember that the cation comes first and
then the anion. Place the correct subscripts behind the ions to get a neutral formula. Place parentheses around any
polyatomic ions that need to be multiplied.
When you have made a formula, click on the “Check” button to see if you have it correct. If you are successful, click on
the “=>” button to advance. If you are not successful, rearrange the formula and try again.
Do this for 5 formulas, writing the ions and correct formula below.
1. Ions: _____________________________ Formula: ___________
2. Ions: _____________________________ Formula: ___________
3. Ions: _____________________________ Formula: ___________
4. Ions: _____________________________ Formula: ___________
5. Ions: _____________________________ Formula: ___________
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You will now explore some common properties that ionic compounds.
Property #1: Ionic Compounds are Hard & Brittle
Ionic compounds have similar characteristics. They are all hard and brittle.
1.) Look up the following ionic compound images on Wikipedia. (If you are on my DP, you can click on the links to access
the information).
Potassium iodide - http://en.wikipedia.org/wiki/File:Potassium_iodide.jpg
Calcium fluoride - http://en.wikipedia.org/wiki/File:Calcium_fluoride.jpg
Aluminum chloride - http://en.wikipedia.org/wiki/File:Aluminium-trichloride-hexahydrate-white-and-yellow.jpg
Calcium nitrate - http://en.wikipedia.org/wiki/File:Dusi%C4%8Dnan_v%C3%A1penat%C3%BD.JPG
2.) What physical properties do all these compounds have in common with each other? What common substance do
these materials remind you of? Why do you think these compounds look similar to each other?
3.) Click on the following link - http://en.wikipedia.org/wiki/File:Halit-Kristalle.jpg. It is a close-up of what salt (sodium
chloride) looks like. Describe what you see.
4.) If you were to smash salt with a hammer, what do you think would happen?
5.) Why do you think ionic compounds are so hard and brittle (break easily)? Go to this website
http://misterguch.brinkster.net/ionic.html and go to the section “ionic compounds are very hard and very brittle.” Read
the answer the author gives for why ionic compounds have these characteristics. Summarize the author’s answer below
in your own words.
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Property #2: Ionic Compounds are Crystals
A crystal or a crystalline solid is a solid material made up atoms, molecules or ions that are arranged in an orderly,
repeating pattern that extends in a 3D direction. Ionic compounds all have a crystalline shape.
Go to the following website to see what a crystalline structure looks like.
http://auden.webster.edu/~scottsus/nacl.htm
Draw what a sodium chloride (NaCl) looks like under the microscope:
Property #3: The Melting Points of Ionic Compounds
One way to identify a material is to see what its melting point is. Every material has a unique melting point. For
example, the melting point of ice is always 0 degrees Celsius or the melting point of mercury is 234 Kelvin.
Ionic bonds or the bonds between ionic compounds are the strongest type of bond between atoms that you can have.
As a result of the really strong bond between ions, the melting point of materials is affected.
Look up the melting points for the following compounds by googling the compound and its melting point (should be the
first thing that comes up on google):
Ionic Compounds
Melting Points (degrees
Celsius)
Non-Ionic Compounds
(Covalent Compounds)
Sodium Chloride (NaCl)
Water (H2O)
Zinc Sulfide (ZnS)
Ammonia (NH3)
Iron Chloride (FeCl3)
Methane (CH4)
Calcium Nitrate (Ca(NO3)2)
Carbon Monoxide (CO)
Iron Sulfide (FeS)
Carbon Tetrafluoride (CF4)
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Melting Points (degrees
Celsius)
What do you notice about the melting points of ionic compounds versus the melting points of non-ionic compounds?
Why do you think the melting points of ionic compounds are different from the non-ionic compounds? HINT: think
about the strengths of bonds between atoms! (HINT: when you melting something, you are breaking the bonds between
atoms. Another reminder- ionic bonds are stronger than non-ionic bonds…)
Property #4: Ionic Compounds Dissolve in Water
A solution is a mixture of a solvent and solute. When an ionic compound is put into water, it dissolves and creates a
solution. Because ionic compounds are able to break apart and dissolve in water, we call them soluble.
1.) When an ionic compound like NaCl, for example, is put into water, it breaks apart into positive and negative ions.
What ions would NaCl break apart into?
2.) In water, what will the Na+ ions be attracted?
3.) In water, what will the Cl- ions be attracted to?
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4.) Now watch this youtube video called “How does salt dissolve in water?” Write a summary of what you see
happening.
http://www.youtube.com/watch?v=dr4sFNzUVzI&feature=fvsr
5.) Watch the youtube video called “Dissociation of NaCl.” Write a summary of what you see happening.
http://www.youtube.com/watch?v=CLHP4r0E7hg&feature=related
Property #5: Ionic Compounds Conduct Electricity in Water
Since ionic compounds dissolve in water, the positive and negative ions simply wander all over the water. Electricity, by
definition, is simply the movement of electrons through a material. In our house, electricity or electrons flow through
wires.
Since ionic compound are positive and negative ions that separate and flow in water, it is easy to allow electrons to
move around and create electricity.
Go to this website: http://www.chem.ufl.edu/~itl/2051_s97/week_1/ionic.html
1. Look at Picture A. Distilled water is pure water- it is water that does not have anything dissolved in it. Why doesn’t
distilled water conduct electricity?
2. Look at Picture B, which is a picture of salt in solid form. Why doesn’t salt as a solid not conduct electricity?
3. Look at Picture C, which is salt dissolved in water. Why does salt dissolve in water conduct electricity?
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Homework- Reflection on Ionic Compounds
Type up a 1-page reflection answer the following questions. When you are done, please email or share the document
with Caroline by Thursday, 8:30 AM.
1.) Explain how ionic bonding works.
2.) What common physical properties do ionic compounds have? Why are they like this?
3.) What do ionic compounds have in common in regards to their melting points? Why are all there melting points like
this? (Hint- has to do with their ionic bonds).
4.) What happens when you put ionic compounds in water?
5.) Why do ionic compounds in water conduct electricity?
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