Chemistry Water B Reading
Name_______________________________
Read pages 25-30.
1. Did preliminary water sample analysis show a likely cause for the fish kills?
2. What does DO stand for? How is this related to fish kills?
3. What are 2 factors EPA chemists will have to consider when examining the possibility that a dissolved
substance may be responsible for the fish kill?
4. Was any illness reported from drinking water in Riverwood?
5. Define “physical properties”.
6. One ______________ of water at 25°C has a mass of one ________________.
7. One __________________ of volume = ____________________ (See figure 1.20)
8. What is the freezing point of water?
9. Why is water that seems pure never really entirely so?
10. What is an aqueous solution?
11. Pure water is clear, __________________________, __________________________, and
______________________________.
12. Please answer the questions B.2 on page 28 here:
1.
2.
3.
1
13. Which state of matter (solid, liquid, or gas) is usually the densest form of a substance? (Note! water is an
exception to this!)
14. Define “mixture”.
15. A solution is a ____________________________ mixture in which the particles are so small they cannot be
seen even with magnification.
16. Define “solute”.
17. Define “solvent”.
18. Describe a suspension:
19. Describe a colloid:
20. Why is milk a colloid?
21. What is the Tyndall effect?
22. If the Tyndall effect is apparent, the mixture is a ____________________________.
If you cannot see the Tyndall effect, the mixture is a ___________________________.
Note: study the chart on page 30!!
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Water Part B
Physical properties of water
 ______________molecules dissolve many substances
 Clear, colorless, odorless, tasteless
 Boiling point = ______________
 Melting/freezing point = ___________
 Density = ________________
 Density of liquid water _____density of ice
 High _________________ _______________
Most solids sink in their liquids!
Defining matter according to makeup



Homogeneous- ____________________properties throughout
Heterogeneous- has parts with ___________________properties
Appearance alone cannot always distinguish heterogeneous matter from homogeneous.
Heterogeneous Matter


Made of more than one type of substance.
Easily separated by _______________________such as evaporation, magnetic separation, or
picking pieces apart.
What is a mixture?
 2 or more substances, ___________________combined
 Mixtures may be __________________or _________________________
 Homogenous mixtures are called ___________________
3
Salt waterHomogeneous mixture,
Solution
How do we know
this is a mixture?
It can be separated
by physical means:
evaporation.
Other examples of solutions
Rootbeer is a solution of
water, sugar, carbon
dioxide, and other
flavorings

Brass is a solution of
Copper and zinc
Air is a _________________
It is a homogenous mixture of nitrogen, oxygen, carbon dioxide and other gases.
Homogeneous matter
 Homogeneous matter may be ________________or________________.
 Pure substances ____________________be separated by physical means. A
____________________ ____________________must occur to separate the parts.
 Pure substances are ________________if they are separable by chemical means. They are
_________________if they can not be further broken down.
4

Water is a pure substance
Water (H2O) can be broken into ____________________and ________________________by
electrolysis. It cannot be separated into hydrogen and oxygen by any physical method.
Hydrogen gas is a pure substance
 Hydrogen may be a ________________(H2) or an _____________________(H). Hydrogen
gas as it normally exists is the compound H2 .
Classifying matter according to make-up
Pure Substances
Compounds
Elements
Mixtures
Homogeneous
Solutions
or Colloids
Heterogeneous
Suspension
What type of matter?
Classifying mixtures by particle size
 _________________: particles too small to see or separate out. No Tyndall effect.
 _________________: Tiny particles produce a cloudy appearance. Shows Tyndall effect
 _________________: Big particles you can see and that will settle out.
5
Solutions
 ________________________mixtures
 Have different parts which are uniformly distributed and are too small to distinguish with the
eye.
 Examples:____________________________________
 Solid solutions are called________________; they are a mixture of metals
 Examples: ________________________________________
 Made of 2 parts- solute and solvent
 ____________________dissolve in things
 _____________________do the dissolving
Colloids
 Can’t see the particles
 Foggy or _________________appearance
 Show Tyndall effect
Particles too
small to
see, evenly
distributed,
cloudy
appearance
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Suspensions
 Particles _____________enough to see and settle out
Many medicines are suspensions
Rivers have particles suspended
in their water
Particles big
enough to see
that may
settle out
Colloid, suspension, or solution?
7
CLASSIFYING MATTER FLOWCHART
8
Water B-2
Atoms and molecules, Polar molecules, Ions and Chemical formulas
Let’s review the molecule!

2 or more atoms ______________ __________together make a molecule.
Let’s review the molecule!
The water molecule consists of ________ hydrogen atoms, and __________oxygen atom.
Its formula is _________________
The ethane molecule consists of ________carbon atoms and __________ hydrogen
atoms.
Its formula is ______________________
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Let’s review molecular formulas:

How many atoms of each element are in the following molecules?
1. H2SO4 __________________________________
2. Ca(OH)2 __________________________________
3. NaCl __________________________________
4. (NH3)3P04 __________________________________
5. 3 H2O (this means 3 water molecules)
__________________________________
6. 4 Al2(CO3)3 (4 aluminum carbonate molecules)
__________________________________
Do an atom inventory for this equation:

NaOH + HCl  NaCl + H2O
Interpret this equation in terms of molecules

(Tell in words what is happening in this reaction)
 2H2
+ O2  2H2O
_________________________________________
______________________
Do an atom inventory:
 2H2 + O2  2H2O
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Interpret this equation in terms of molecules
3N2 + H2  2 NH3
_________________________________________________
_____________________________
Interpret this equation in terms of molecules:
Do an atom inventory
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Please read pages 34-36 in your text and do the exercises B.7 #1-3 on pages 3637 here, then also answer questions 4 - 6 on the next page:
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4. What are diatomic molecules?
5. List the elements that exist as diatomic molecules.
6. Look up these elements on your periodic table. Trace the positions of all except hydrogen. What shape do
they make ( if you don’t include hydrogen)?
It will be easy to remember them, because there are 7 elements and they make the number 7 on the periodic
table (plus you have to remember hydrogen!)
Or, you can just remember the magic word…
HNOFClBrI
Ions and chemical formulas
Let’s review the atom:




The atom has 3 subatomic particles
_________-in the nucleus, + charge
_________- in the nucleus, neutral
__________- outside the nucleus, - charge (moving!)
IONS
Elements that have gained or lost an electron
 Cations are positive


 They
have lost an electron
 They
have gained an electron
Anions are negative
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Is this sodium ion a cation or
an anion?
Chlorine gains an electron when it
ionizes. Is it a cation or an anion?
When the two combine, you get sodium chlorideeverybody’s happy!
Ionic bonds


Na+
ClMakes the ionic compound ________________
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Question:
Calcium prefers to lose 2 electrons. What kind of ion would
calcium be?
 ____________, a ____________________

Question:
 Fluorine would like an extra electron. What kind of ion will it
become?
 ____________, a fluoride ___________________
Question:
 What compound is made from calcium and fluoride ions?
 Calcium fluoride, _______________
Question: Why are 2 F’s needed for one Ca?
 FCa2+ F- The charges need to______________________!

Atoms prefer a full outer shell of electrons!
Draw some atoms and ions!

Draw some atoms as Neils Bohr represented them. Then you will draw
some ions as you see if atoms prefer to gain or lose electrons to fill their
outer shell.
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Names and formulas of ionic compounds
 Molecular-
______________bonds, electrons are
_____________
 Ionic- ionic bonds, electrons are _________________
 Ionic
Covalent or ionic?
bonds form between a _________and a ________________
 Covalent
bonds form between 2 ______________or a nonmetal and
____________

Na and Cl

C
and H
Covalent or ionic?
________________
_______________________________
C
and S
_____________________________________
N
and N
________________________________________
 Ca
and S
___________________________________________
 Fe
and Cl
____________________________________________
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Naming ionic compounds

The first name is the name of the _______________
– Example: CaCl2 has first name ______________

The last name has the name of the____________. Anion names always
end in “__________” unless they are from your polyatomic ion chart.
– Example: CaCl2 has last name chloride,
so is CaCl2 __________________ ____________
1.
 2.
 3.
 4.
 5.

Name these ionic compounds
BaF2_________________________________
K2Se_________________________________
CaS__________________________________
AlF3_________________________________
LiH__________________________________
1) MgS ___________________________
2) KBr ____________________________
3) Ba3N2 ___________________________
4) Al2O3 ___________________________
5) NaI ____________________________
6) SrF2 _____________________________
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 Some
Naming ionic compounds-more
compounds need __________ _______________________to
distinguish between possible first names.
 For example, a compound of iron and chloride may be iron (II) chloride or
iron (III) chloride.
 The roman numeral is equal to the ___________on the ion
Name these ionic compounds using roman numerals:
1. A compound of Mn3+ and Cl________________________________

 2.
NiN
_________________________________
 3.
SnO
____________________________________________
 4. SnO2
_______________________________
 5.
PbO
_________________________________
 CrCl3
 ______________________________________
 CoO
 ______________________________________
 Mn2O3
 ______________________________________
 Co2S3
 ______________________________________
 AuF
 ______________________________________
 CrBr2
 ___________________________________________________
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Which elements need roman numerals in their names?
 Any
 All
elements listed as _________________metals
________________________metals except zinc, cadmium, and silver.
– Zinc and cadmium always form _________ions, silver always forms a
___________ion.
Naming ionic compounds that contain more than 2 elements
 Compounds
containing polyatomic ions are named by using your
_____________ __________chart.
Name these ionic compounds that contain polyatomic ions:
 1.
NH4Cl
 __________________________________
 2.
NH4OH
– __________________________________

3. (NH4 )3PO3
_____________________________________________________________

4. AlPO4
– ________________________________

5. Fe(NO2) 2
_________________________________
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 1.
N a Cl
Mixed practice naming ionic compounds!
________________________________________________________

2. Fe2O3
_________________________________________________________

3. CuCl2
__________________________________________________________
 4.
CuCl
__________________________________________________________

5. (NH4)2CO3
___________________________________________________________

6. Ca3(PO4) 2
____________________________________________________________
Rule for writing ionic formulas:
________________________________________________________________________
Practice writing ionic formulas

1. Ca2+ combined with F-_____________________

2. Co3+ combined with PO43-_______________________

3. Ni2+ combined with OH-______________________
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More practice

1. calcium combined with oxygen

____________________________

2. potassium combined with oxalate

_____________________________

3. chromium (II) hydrogen sulfate
__________________________________________________
Write formulas for these!
Tin (II) oxide ____________________
Tin (IV) oxide ____________________
Tin (II) hydroxide ____________________
Tin (II) dichromate ____________________
Tin (II) phosphate ____________________
Ammonium phosphite ____________________
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NAMING COVALENT (MOLECULAR) COMPOUNDS
22
LAB B8 Water Testing
1. Define:
a. Qualitative tests:
Read pages 42- 45
b. Quantitative tests:
c. Precipitate:
2. Cations:
a. definition: (from previous notes)
b. the cations we will be testing for in this lab are:
c. Why must we call the iron ion we will be testing for “iron III”?
3. Anions:
a. definition: (from previous notes)
b. the anions we will be testing for in this lab are:
4. Why are you using distilled water as one of the solutions that you will test?
5. What is a reference solution?
6. List the 4 reference solutions you will use. The reference solutions are named the same as the
ions for which you will be testing.
7. Since the reference solutions contain the ions we are testing for, should you always see some sort
of reaction when you test the reference solutions?
8. What will you use as your unknown solutions?
9. How will you tell if the ion you are testing for is present in the tap water?
10. Will any ions be present in the distilled water? If not, then why are you testing for them?
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Read suggestions on page 43!!!
GOGGLES ARE REQUIRED!!!!!!
All solutions except distilled, tap water and natural water are in pipettes.
Thoroughly wash, rinse, and dry 3 small beakers. Put distilled water in one, tap water in another,
and natural (pond) water in the third.
Follow procedures in book.
CLEAN UP: Rinse excess chemicals in pipettes down drain with tap H20 running. Rinse insides of
pipettes thoroughly with tap water twice and then with distilled water. DO NOT DISCARD
PIPETTES!!
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Naming Ionic Compounds
Name These:
1. MgCl2 _________________
2. K2O____________________
3. Be3S2 __________________
4. NH4Cl __________________
5. NH4OH_________________
6. Ba(CN) 2 _________________
7. Na2SO3 _________________
8. (NH4) 3PO4 _______________
9. (NH4) 3PO3 ______________
10. NaBr ___________________
11. NH4Br _______________
12. H2O ___________________
13. Ar ____________________
14. CuSO4 __________________
15. CuOH _________________
16. Cu(OH) 2 _________________
17. Pb(OH) 2 _______________
18. Pb(OH) 4 _________________
19. MnSO4 ________________
20. MnPO4 __________________
21. SnO___________________
22. SnO2____________________
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Write formulas for these ionic compounds:
1. Calcium hydroxide: _____________
2. Calcium bromide: ______________
3. Copper (I) sulfate: ______________
4. Copper (II) sulfate: ______________
5. Ammonium nitrate: ______________
6. Tin (II) oxide: __________________
7. Tin (IV) oxide: _________________
8. Chromium (II) dichromate: ______________
9. Barium Phosphate ______________
10. Ammonium Carbonate: ______________
11. Strontium bromide________________
12. Cadmium sulfide ____________________
13. Cadmium phosphate___________________
14. Iridium (III) oxide ___________________
15. Iridium (II) phosphate_________________
16. Vanadium(IV) phosphide_______________
18. Mercury(I) selenide___________________
19. Mercury(I) selenate____________________
20. Mercury(II) selenate___________________
26
Chem worksheet: names
Your name is:________________________________
Write the correct chemical name for:
1) MgS
2) KBr
3) Ba3N2
4) Al2O3
5) NaI
6) SrF2
7) Li2S
8) RaCl2
9) CaO
10) AlP
11) K2S
12) LiBr
13) Sr3P2
14) BaCl2
15) NaBr
27
Write the correct name for: (these need roman numerals)
1) CuS
2) PbBr4
3) Pb3N2
4) Fe2O3
5) FeI2
6) Sn3P4
7) Cu2S
8) SnCl2
9) HgO
10) Hg2F2
11) CuCl2
12) CuBr
13) PbO
14) Fe2S3
15) PbCl2
16) SnO
17) Cu2O
18) PbO2
19) FeO
20) SnO2
21) Hg2O
22) Hg2I2
23) AuCl3
24) MnO
28
POLYATOMIC IONS: Write the correct name for:
1) AlPO4
2) KNO2
3) NaHCO3
4) CaCO3
5) Mg(OH)2
6) Na2CrO4
7) Ba(CN)2
8) K2SO4
9) NaH2PO4
10) NH4NO3
These formulas involve the use of a polyatomic ion. The cations are all of variable
oxidation state, so Roman numerals are needed.
Write the correct name for:
11) Sn(NO3)2
12) FePO4
13) Cu2SO4
14) Ni(C2H3O2)2
15) HgCO3
16) Pb(OH)4
17) Cu2Cr2O7
18) Cu(ClO3)2
19) FeSO4
20) Hg2(ClO4)2
29
Chemical Formula Writing Worksheet
Write chemical formulas for the compounds in each box. The names are found
by finding the intersection between the cations and anions. Example: The first
box is the intersection between the “zinc” cation and the “chloride” anion, so you
should write “ZnCl2”, as shown.
zinc
chloride
iron (II)
iron (III)
gallium
silver
lead (IV)
ZnCl2
acetate
nitrate
oxide
nitride
sulfate
Write the formulas for the following compounds:
1)
copper (II) chloride ____________________________________
2)
lithium acetate ____________________________________
3)
vanadium (III) selenide ____________________________________
4)
manganese (IV) nitride ____________________________________
5)
beryllium oxide ____________________________________
6)
sodium sulfate ____________________________________
7)
aluminum arsenide ____________________________________
8)
potassium permanganate ____________________________________
9)
chromium (VI) cyanide ____________________________________
10)
tin (II) sulfite ____________________________________
11)
vanadium (V) fluoride ____________________________________
12)
ammonium nitrate ____________________________________
30
Polyatomic Ions
Note: The charge on the ions below is the net charge. For example, PO4 has a -3 charge
because the oxidation number of the oxygen (O4) is -2 x 4 = -8 and the oxidation
number of the phosphorus (P) is +5.
-8 + 5 = -3. Therefore, when writing formulas
with polyatomic ions, simply use the charge given in the column above the ion.
+1 ion
-1
Formula
Name
Formula
NH4
Ammonium
H2PO4
C2H3O2
HSO3
HSO4
HCO3
NO2
NO3
CN
OH
MnO4
ClO
ClO2
ClO3
ClO4
SCN
-2
Formula
HPO4
C2O4
SO3
SO4
CO3
CrO4
Cr2O7
SiO3
SeO4
ions
Name
Dihydrogen phosphate
Acetate
Hydrogen sulfite (or bisulfite)
Hydrogen sulfate (or bisulfate)
Hydrogen carbonate (or bicarbonate)
Nitrite
Nitrate
Cyanide
Hydroxide
Permanganate
Hypochlorite
Chlorite
Activity series of metals
Chlorate
Li
Lithium
Perchlorate
K
Potassium
Thiocyanate
Ba
Barium
Ca
Calcium
ions
Na
Sodium
Mg
Magnesium
Name
Al
Aluminum
Hydrogen phosphate
Zn
Zinc
Oxalate
-3
ions
Fe
Iron
Sulfite
Formula
Name
Ni
Nickel
Sulfate
Sn
Tin
Carbonate
PO4
Phosphate
Pb
Lead
Chromate
PO3
Phosphite
(H)
Hydrogen
Dichromate
Fe(CN)6
Ferricyanide
Cu
Copper
Silicate
Hg
Mercury
Selenate
Ag
Silver
Acid names
Au
Gold
anion
acid name
ending
(metals from Li to Na will replace H
-ide
-ite
-ate
hydro----ic acid
-------ous acid
-------ic acid
from acids and water, from Mg to Pb
they will replace H from acids only)
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