Download 104 Homework Packet - Rogue Community College

CHEMISTRY 104
Rogue Community College
HOMEWORK SHEETS
to be used with General, Organic and Biochemistry, 2nd edition, by Janice Gorzynski Smith
Classification of Matter (CH. 1) ….……………………………………………….....
3
Significant Figures (CH. 1) ……..….…………………..……………………………...
5
Unit Conversions (CH. 1) …………………..…..…..………………………………...
7
Temperature Scales (CH. 1) ……………………….…………………………………..
9
Atoms and Formulas (CH. 2) ………………….……...……………………………….
11
Atomic Structure (CH. 2) ………..…………………...……………………………….
13
Periodic Table (CH. 2) …………………………………….…………………………..
15
Chemical Bonding (CH. 3&4) ………...………………………..………...…………...
17
Naming and Formula Writing (CH. 3&4) ……………………………..……………...
19
Molecular Geometry (CH. 4) …………………………………….………..……………
21
Balancing Equations (CH. 5) ………………..……………..…………………………..
23
Moles (CH. 5) ………………………………………………………………….………
25
Stoichiometry (CH. 5) …….…………………………………………………………...
27
Energy (CH. 6) ………………….………………………………………...……………
29
Reaction Rate (CH. 6) ………………………………………………………..………..
31
Gas Laws (CH. 7) ……………………………………………………………………..
33
Intermolecular Forces (CH. 7) ……………………………………………...…….…..
35
Solutions (CH. 8) ….……………………………………………………………….....
37
Acids and Bases (CH. 9) ….…………………………………………………….….....
39
Neutralization and Buffers (CH. 9) ….……………………...…………………..….....
41
1
2
Chemistry 104 – Rogue Community College
Classification of Matter Homework
Name ___________________________
Distinguish between each of the following pairs of terms. Do not use examples!
1.
mass and weight
2.
element and compound
3.
substance and mixture
4.
physical change and chemical change
5.
liquid and gas
3
6.
Classify each of the following as an element, a compound or a mixture:
water
_______________
cheese
_______________
mercury
_______________
air
_______________
sugar
_______________
salt
_______________
oxygen
_______________
aluminum
_______________
helium
_______________
brass
_______________
vinegar
_______________
coffee
_______________
steel
_______________
iron
_______________
steam
_______________
ice
_______________
ice cream
_______________
seawater
_______________
methane
_______________
copper
_______________
granite
_______________
blood
_______________
arsenic
_______________
krypton
_______________
4
Chemistry 104, Rogue Community College
Significant Figures Homework
Name ___________________________
Part One.
Record each of the following three measurements to the appropriate number of
significant figures. Include the appropriate units.
Centimeter Ruler:
1
2
3
5
4
6
5.5
5.0
3.96
4.00
5
Part Two.
Rewrite the following measurements using scientific notation. Do not change the units.
1.
0.00573 g
-------->
2.
0.45400 kg
-------->
3.
12055 years
-------->
4.
93,000,000 miles
-------->
Part Three.
Write down the number of significant figures in each of the following
measurements.
1.
0.00503 g
-------->
2.
500 miles
-------->
3.
1.75 yards
-------->
4.
0.75 yards
-------->
5.
1.00 x 10-10 m
-------->
6.
93,000,000 miles
-------->
7.
6.022 x 1023 atoms
-------->
Part Four.
Perform each of the following calculations. Record each answer to the correct
number of significant figures and in the correct units.
3.75 g
=
2.24mL
_______________
2.75cm x 2.74cm =
_______________
2.05 g
= _______________
0.2900 g
11.29 g  1.4 g =
_______________
12.3 g
=
5
11.29 g  1.4cg =
_______________
_______________
6
Chemistry 104, Rogue Community College
Unit Conversions Homework
Name ___________________________
Set up and solve the problem in the space provided. Show all of your work!
1.
Convert the measurement 92.0 g into pounds. (1 lb = 453.6 g)
2.
Convert the measurement 92.0 cm into inches. (2.54 cm = 1 in)
3.
Convert the measurement 2.15 mi into kilometers. (1 mi = 1.609 km)
4.
Convert the measurement 0.001065 metric tons into grams. (1 metric ton = 1 x 106 g)
5.
Convert the measurement 0.0039 L into cm3. (1 cm3 = 1 mL)
7
6.
Convert the measurement 45.0 mg into grams.
7.
Convert the measurement 45.0 g into milligrams.
8.
Convert the measurement 1.25 L into milliliters.
9.
Convert the measurement 15.0 cm into mm.
10.
Convert the measurement 125 g into g.
11.
Convert the measurement 0.0058 m into cm.
8
Chemistry 104, Rogue Community College
Temperature Scales Homework
Name ___________________________
There are three common temperature scales: Fahrenheit (F), Celsius (C) and kelvins (K).
It is easiest to convert between kelvins and Celsius: TK = Tc + 273.15 or Tc = TK  273.15.
It is also straightforward to convert between Celsius and Fahrenheit: TF = 1.8(Tc) + 32
or Tc = (TF  32)(5/9).
To convert between kelvins and Fahrenheit, it is easiest to do it in two steps: first convert from
kelvins to Celsius and then from Celsius to Fahrenheit, or first convert from Fahrenheit to
Celsius and then from Celsius to kelvins.
Practice using the above equations on the following temperature conversions:
1.
Convert normal body temperature (98.6F) into Celsius.
2.
Convert the freezing point of water (0C exactly) into kelvins.
3.
Convert room temperature (25C) into Fahrenheit.
4.
Convert absolute zero (0 K exactly) into Celsius.
9
5.
Convert the temperature of liquid nitrogen (77 K) into Celsius and Fahrenheit.
6.
Convert the temperature of dry ice (78.5C) into Fahrenheit and kelvins.
7.
Convert the temperature of the surface of Venus encountered by Soviet spacecraft (about
465C) into Fahrenheit and kelvins.
8.
Choose a temperature that is of interest to you for some reason. What makes this
temperature interesting? Express this temperature in C, F and K.
10
Chemistry 104, Rogue Community College
Atoms and Formulas Homework
Name ___________________________
1.
2.
Classify each of the following elements as a metal, nonmetal or metalloid.
(a)
lithium (Li)
____________________________
(b)
beryllium (Be)
____________________________
(c)
boron (B)
____________________________
(d)
carbon (C)
____________________________
(e)
nitrogen (N)
____________________________
(f)
oxygen (O)
____________________________
(g)
fluorine (F)
____________________________
Fill in the blanks to accurately complete the following statements about the structure of
the atom.
(a)
All atoms of the same element have the same number of ________________ in
the ________________.
(b)
The subatomic particle with no electrical charge is called the ________________.
(c)
When an atom has no overall electrical charge, it has the same number of
________________ and ________________.
(d)
Atoms of the same element that have different weights are called
________________ of that element.
11
3.
Distinguish between the terms atomic number and mass number. Do not use examples!
4.
Write the chemical formula for a compound that contains:
5.
(a)
two atoms of hydrogen and one atom of oxygen
(b)
one atom each of carbon and oxygen
(c)
two atoms of hydrogen, one atom of carbon and three atoms of oxygen
(d)
two atoms of potassium, one atom of sulfur and four atoms of oxygen
(e)
three atoms of sodium, one atom of phosphorus and four atoms of oxygen
How many of each kind of atom are present in each of the following formulas?
(a)
KOH
K=
(b)
Cl =
Mg3(PO4)2
Mg =
(d)
H=
AlCl3
Al =
(c)
O=
P=
O=
H=
S=
(NH4)2SO3
N=
12
O=
Chemistry 104, Rogue Community College
Atomic Structure Homework
Name ___________________________
1. How many protons, neutrons and electrons are there in each of the following species?
(a)
(d)
2.
12
6
C
238
92
U
p+
(b)
14
6
C+
p+
(c)
1
1
H-
p+
n0
n0
n0
e-
e-
e-
p+
(e)
23
11
Na +
p+
(f)
32
16
S2-
p+
n0
n0
n0
e-
e-
e-
Give one example of (a) an isotope of carbon-12, (b) an ion that is isoelectronic with
neutral carbon-12, (c) an atom that has the same number of protons as carbon-12, (d) an
atom that has the same number of neutrons as carbon-12, and (e) an atom that has the
same number of nucleons as carbon-12.
13
3.
Write the complete symbol ( ZA E chg ) for an atom that contains 15 protons, 17 neutrons and
15 electrons. (Write the correct atomic symbol in your answer, not E!!)
4.
Write the complete symbol ( ZA E chg ) for an atom that contains 1 proton, no neutrons and
no electrons. (Write the correct atomic symbol in your answer, not E!!)
5.
Write the complete symbol ( ZA E chg ) for an atom that contains 82 protons, 125 neutrons
and 80 electrons. (Write the correct atomic symbol in your answer, not E!!)
6.
Write the electronic configuration for each element.
7.
(a)
lithium
_______________________________________________
(b)
carbon
_______________________________________________
Name the element with each of the following electronic configurations.
(a)
[He] 2s2
______________________________
(b)
[Ne] 3s23p1
______________________________
(c)
[Ar] 4s1
______________________________
14
Chemistry 104, Rogue Community College
Periodic Table Homework
Name ___________________________
1.
Distinguish between a group and a period on the periodic table.
2.
Give one example of each of the following:
alkali metal =
halogen =
noble gas =
metalloid =
alkaline earth metal =
transition metal =
lanthanide =
an element used by the thyroid gland to make thyroxine =
an element whose forms include diamond, graphite and buckminsterfullerene =
an element in the p-block of the periodic table that is not a halogen, noble gas or
metalloid =
15
3.
How many electrons can the first energy level (or shell) in an atom hold?
4.
How many electrons can the fifth energy level in an atom hold? (hint: use 2n2)
5.
How many valence electrons are there in a neutral oxygen atom?
6.
How many valence electrons are there in a neutral sodium atom?
7.
How many valence electrons are there in a neutral carbon atom?
8.
How many valence electrons are there in a potassium ion, K+?
9.
How many valence electrons are there in a calcium ion, Ca2+?
10.
Which group of atoms has a stable octet of valence electrons?
11.
Distinguish between an s-orbital and a p-orbital.
12.
Comparing C and F, which atom has the larger radius? Which has the higher ionization
energy?
13.
Comparing N and P, which atom has the larger radius? Which has the higher ionization
energy?
16
Chemistry 104, Rogue Community College
Chemical Bonding Homework
Name ___________________________
1.
2.
Draw the electron-dot symbol for each of the following atoms:
arsenic, As
iodine, I
rubidium, Rb
beryllium, Be
gallium, Ga
silicon, Si
helium, He
radon, Rn
oxygen, O
nitrogen, N
Draw electron-dot symbols for the ions in each of the following binary ionic compounds:
sodium chloride, NaCl
magnesium oxide, MgO
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3.
Explain the octet rule in your own words.
4.
Briefly explain why hydrogen does not follow the octet rule.
5.
Distinguish between ionic and covalent bonds.
6.
What is a polyatomic ion? What makes it different from a molecule? What makes it
different from a monatomic ion? (Include an example of each in your answer.)
7.
Draw a valid Lewis structure for each of the following molecules:
oxygen, O2
iodine, I2
water, H2O
methane, CH4
phosphorus trichloride, PCl3
oxygen dichloride, OCl2
18
Chemistry 104, Rogue Community College
Naming and Formula Writing Homework
Name ___________________________
Name each of the following compounds:
H2CO3
______________________________________________
NaHCO3
______________________________________________
CO2
______________________________________________
SCl2
______________________________________________
Zn3(PO4)2
______________________________________________
AgI
______________________________________________
TiF4
______________________________________________
Cr(ClO3)3
______________________________________________
Al2S3
______________________________________________
H2O
______________________________________________
NBr3
______________________________________________
Fe(OH)2
______________________________________________
CBr4
______________________________________________
H2SO4
______________________________________________
19
Write the correct formula for each of the following compounds:
hydrochloric acid
______________________________
magnesium chloride
______________________________
aluminum phosphate
______________________________
ammonium hydroxide
______________________________
ammonium carbonate
______________________________
dinitrogen trioxide
______________________________
dinitrogen tetroxide
______________________________
dinitrogen pentoxide
______________________________
sulfur dioxide
______________________________
sulfuric acid
______________________________
potassium bicarbonate
______________________________
ammonium cyanide
______________________________
calcium hydrogen phosphate
______________________________
iron (III) cyanide
______________________________
silver oxide
______________________________
nitric acid
______________________________
20
Chemistry 104, Rogue Community College
Molecular Geometry Homework
Name ___________________________
Molecular
Formula
Number
of v.e.
Lewis Structure
H2O
NH3
CH4
CH2F2
HCN
CO2
21
Shape
Polar or
Nonpolar?
Molecular
Formula
Number
of v.e.
Lewis Structure
Cl2O
BF3
H2CO
(formaldehyde,
C in the center)
NF3
H2S
C2H4
(ethylene,
H2C=CH2)
22
Shape
Polar or
Nonpolar?
Chemistry 104, Rogue Community College
Balancing Equations Homework
Name ___________________________
Balance each of the following equations by placing an integer coefficient on each of the blank
lines:
___ KNO3
---------->
___ NH4NO2 ---------->
___ O2 
___ KNO2
+
___ N2
___ H2O
+
___ MgO
+
___ H2O
---------->
___ Mg(OH)2
___ Fe2O3
+
___ CO
---------->
___ Fe +
___ CaO
+
___ P2O5
---------->
___ Ca3(PO4)2
___ MgCl2
+
___ AgNO3
---------->
___ Mg(NO3)2
___ Cu
___ H2SO4
+
___ K2CO3
+
--------->
___ BaCl2
___ CuSO4
---------->
+
___ KCl
___ Mg(OH)2 + ___ (NH4)3PO4 ---------->
23
___ CO2
+
___ SO2 +
+
___ AgCl
___ H2O
___ BaCO3
___ Mg3(PO4)2 + ___ NH3 + ___ H2O
Note: Be very careful about writing chemical formulas! If your formulas are wrong, you may
come up with an equation that is impossible to balance!!
methane + oxygen
--------> carbon dioxide + water
magnesium oxide + carbon dioxide --------> magnesium carbonate
magnesium oxide --------> magnesium + oxygen
water + carbon dioxide --------> carbonic acid
water + diphosphorus pentoxide --------> phosphoric acid
water + sodium oxide --------> sodium hydroxide
24
Chemistry 104 – Rogue Community College
Mole Homework
Name ______________________________
1.
Calculate the number of moles of O2 in 100.0 g of O2 gas.
2.
Calculate the number of O2 molecules in 100.0 g of O2 gas.
3.
Calculate the number of moles of Ti in 38.2 g of titanium metal.
4.
Calculate the number of Ti atoms in 38.2 g of titanium metal.
25
5.
Calculate the mass of 2.08 moles of CO2.
6.
Calculate the mass of 0.064 moles of C6H12O6.
7.
Calculate the mass of 1 hundred trillion water molecules. (By definition, 1 hundred
trillion = 1 x 1014.) Do you think you could see a sample of water this small?
8.
Proteins can have extremely high molecular weights, up into the thousands and millions
of grams/mole. Calculate the mass of 1 hundred trillion protein molecules if the protein
has a molecular weight of 10,000,000 g/mol. Do you think you could see a sample of
protein this small?
26
Chemistry 104, Rogue Community College
Stoichiometry Homework
Name ___________________________
1.
Balance the following chemical equation, and use it to answer the following questions:
_____ Al (s)
+ _____ O2 (g)
----->
_____ Al2O3 (s)
(a)
What mass of oxygen will react with 2.75 g of aluminum?
(b)
What mass of aluminum oxide will be formed when 2.75 g of aluminum reacts
completely with oxygen?
(c)
Show how your results are consistent with the Law of Conservation of Mass.
27
2.
Hydrogen gas reacts with oxygen gas to form liquid water. How many grams of O2 are
required in order to produce 10.0 g of H2O?
3.
Sodium metal reacts with chlorine gas to form sodium chloride. How many grams of
sodium chloride can be produced from 10.0 g of Cl2?
4.
Methane reacts with oxygen to form carbon dioxide and water. How many grams of
oxygen are required in order to react completely with 10.0 g methane?
28
Chemistry 104, Rogue Community College
Energy Homework
Name ___________________________
1.
2.
Use Table 6.2 on p. 171 to help you answer these questions.
(a)
Which bond is stronger, H-H or F-F?
(b)
Which bond is stronger, H-H or H-F?
(a)
Bond __________________ is always endothermic. (making or breaking)
(b)
Bond __________________ is always exothermic. (making or breaking)
3.
In the reaction H2 + F2  2HF, one H-H bond is broken, one F-F bond is broken and two
H-F bonds are formed. Is the reaction exothermic or endothermic? Explain your
reasoning. (Use the bond dissociation energies in Table 6.2 to help you answer this
question.)
4.
(a)
Slow reactions have __________________ activation energies. (high or low)
(b)
Fast reactions have __________________ activation energies. (high or low)
5.
Catalysts speed up chemical reactions by ________________ the activation energy.
6.
When the forward and reverse rates of a chemical reaction are equal, we say that the
reaction is at _________________________.
29
7.
Distinguish between the terms endothermic reaction and exothermic reaction.
8.
Distinguish between the terms potential energy and kinetic energy.
9.
Distinguish between the terms calorie and Joule.
10.
According to Le Chatelier’s Principle, adding reactants (or removing products) drives the
equilibrium to the __________, adding products (or removing reactants) drives the
equilibrium to the __________, increasing temperature favors the ___________________
reaction, decreasing temperature favors the ____________________ reaction, increasing
pressure shifts the reaction toward _______________ gas molecules, decreasing pressure
shifts the reaction toward ________________ gas molecules, and adding a catalyst has no
effect on equilibrium position whatsoever. (Choices: left/right, endothermic/exothermic,
more/fewer)
30
Chemistry 104, Rogue Community College
Reaction Rate Homework
Name ___________________________
1.
According to molecular collision theory, only collisions that have sufficient energy and
proper orientation lead to a reaction.
(a)
In your own words, explain why sufficient energy is necessary for a reaction to
occur.
(b)
In your own words, explain why proper orientation is necessary for a reaction to
occur.
2.
The transition state is the point of ________________ energy in a molecular collision.
(maximum/minimum)
3.
Sketch a labeled energy diagram for an endothermic reaction with H = 10 kcal/mol and
and Ea = 30 kcal/mol. Be sure to label the axes (energy and reaction coordinate), the
reactants, products, transition state, H and Ea.
31
4.
For a given chemical reaction, state whether each of the following changes will result in a
faster or a slower reaction (circle your answer). Then, explain each answer in terms of
molecular collision theory (collision rates, collision energies and activation energy).
(a)
The concentrations of reactants is decreased.
Faster
Slower
(b)
The temperature is decreased.
Faster
Slower
(c)
A catalyst is added.
Faster
Slower
(d)
The volume of a gas-phase reaction is decreased.
Faster
Slower
(e)
Any solid reactants are crushed.
Faster
Slower
32
Chemistry 104 – Rogue Community College
Gas Law Homework
Name ___________________________
Ideal Gas Law: PV = nRT, where R = 0.08206 Latm/molK
Boyle's Law: P1V1 = P2V2 (n, T constant);
Charles' Law: V1/T1 = V2/T2 (n, P constant)
Gay-Lussac’s Law: P1/T1 = P2/T2 (n, V constant)
Avogadro’s Law: V1/n1 = V2/n2 (T, P constant)
1.
What is the volume of 3.25 moles of ideal gas at 25.0C and 0.759 atm pressure?
2.
What pressure is exerted by 0.25 moles of ideal gas at 50.0C and a volume of 1.75 L?
3.
How many moles of ideal gas will occupy a volume of 20.0 L at 100.C and 0.275 atm?
33
4.
At what temperature (in C) will 1.25 moles of ideal gas occupy a volume of 10.0 L with
a pressure of 0.500 atm?
5.
A fixed quantity of gas at 25.00C occupies 3.75 L. If the gas is heated at constant
pressure to 50.00C, what will its new volume be?
6.
A fixed quantity of gas at 2.75 atm occupies 3.75 L. If the gas is compressed at constant
temperature to 1.75 L, what will its new pressure be?
7.
A 1.25-mol sample of gas occupies 25.0 L at a certain temperature and pressure. What
volume will a 2.25-mol sample occupy at the same temperature and pressure?
8.
A fixed quantity of gas at 300.0 K exerts a pressure of 1.45 atm. If the gas is heated at
constant volume to 350.0 K, what will its new pressure be?
34
Chemistry 104, Rogue Community College
Intermolecular Forces Homework
Name ___________________________
______
______
______
______
______
______
______
______
1.
Which of the following molecules exhibits hydrogen bonding?
(A)
CH4
2.
Which of the following are intermolecular forces?
(A)
dipole-dipole interactions
(B)
London forces
(C)
hydrogen bonding
(D)
all of the above
3.
Which of the following will tend to increase intermolecular forces?
(A)
increased molecular weight
(B)
increased polarity
(C)
increased hydrogen bonding
(D)
all of the above
4.
Choose the substance with the highest boiling point:
(A)
H2O
5.
Choose the substance with the highest boiling point:
(A)
F2
6.
Which state of matter has both definite shape and definite volume?
(A)
solid
7.
Which state of matter has neither definite shape nor definite volume?
(A)
solid
8.
Which state of matter has definite shape but not definite volume?
(A)
solid
(B)
(B)
(B)
(B)
(B)
(B)
PH3
Ne
Cl2
liquid
liquid
liquid
35
(C)
(C)
(C)
(C)
(C)
(C)
H2S
O2
Br2
gas
gas
gas
(D)
H2O
(D)
Ar
(D)
I2
(D)
(D)
(D)
none
none
none
9.
Can nonpolar molecules experience London dispersion forces? Why or why not?
10.
Which types of intermolecular forces are present in HCN? Explain your reasoning.
11.
(a)
Which of the phase changes are endothermic?
(b)
Which of the phase changes are exothermic?
12.
Higher vapor pressures are found in liquids with __________________ temperatures and
____________________ intermolecular forces. (higher/lower, stronger/weaker)
13.
Distinguish between the terms viscosity and surface tension.
14.
Distinguish between the bonding in ionic, molecular, network and metallic solids.
36
Chemistry 104 – Rogue Community College
Solutions Homework
Name ___________________________
1.
A solution is prepared by dissolving 10.0 g of (solid) naphthalene (C10H10) in 500.0 mL
of (liquid) chloroform (CHCl3). The resulting solution is liquid. Identify the solute and
the solvent.
2.
Calculate the molarity of the solution from #1.
3.
Calculate the weight/volume percent concentration of C10H10 in the solution from #1.
4.
What volume of the solution from #1 contains 2.7 g of naphthalene?
5.
How many grams of naphthalene are contained in 25.0 mL of the solution from #1?
37
Remember that for dilution calculations c1V1 = c2V2.
6.
Calculate the final concentration obtained when 150.0 mL of a 0.757 M solution of CaCl2
is diluted to a final volume of 1.000 L.
7.
What volume of 6.00 M HCl should be diluted to a final volume of 500.0 mL in order to
obtain a 1.50 M solution of HCl?
8.
Determine the number of “particles” contained in one mole of each solute, and then rank
the solutions in order of increasing vapor pressure.
0.10 M sucrose (C12H22O11)
0.08 M NaCl
0.03 M MgCl2
9.
Rank the solutions from #8 in order of increasing boiling point.
10.
Rank the solutions from #8 in order of increasing freezing point.
11.
Rank the solutions from #8 in order of increasing osmotic pressure.
38
Chemistry 104 – Rogue Community College
Acids & Bases Homework
Name___________________________________
1.
2.
3.
Write the formula for the conjugate base of each of the following acids:
HC2H3O2
__________
H2O
__________
HCO3−
__________
H3PO4
__________
NH4+
__________
H3O+
__________
Write the formula for the conjugate acid of each of the following bases:
NH3
__________
H2O
__________
HCO3−
__________
F−
__________
PO43−
__________
OH−
__________
Give one example each of a strong acid, a strong base, a weak acid and a weak base.
39
4.
How many grams of H2SO4 are present in 250.0 mL of 0.175 M solution?
5.
What volume of 0.1073 M NaOH contains 0.0250 moles of NaOH?
6.
What is the pH of 0.100 M HCl?
7.
What is the pH of 0.100 M NaOH?
40
Chemistry 104 – Rogue Community College
Neutralization and Buffer Homework
Name___________________________________
Write the net ionic equation for each of the following neutralization reactions.
1.
HCl reacts with NaOH in a neutralization reaction.
2.
H2SO4 reacts with NaOH in a neutralization reaction.
3.
HCl reacts with NaHCO3 in a neutralization reaction.
4.
H2SO4 reacts with NaHCO3 in a neutralization reaction.
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5.
State whether each of the following salts is acidic, basic or neutral.
sodium chloride ________________
sodium acetate _________________
ammonium chloride ______________
potassium nitrate _______________
sodium phosphate _______________
lithium fluoride ________________
For questions #6 and 7, use the equation [H3O+] = Ka[HA]/[A−] or pH = pKa – log[HA]/[A−].
6.
Find the pH of a buffer that contains 0.15 M acetic acid and 0.10 M sodium acetate.
7.
Find the pH of a buffer that contains 0.20 M sodium carbonate and 0.10 M sodium
bicarbonate.
8.
What is the property of a buffer that makes it different from a non-buffer solution?
9.
Why are buffers important in the environment and in the human body?
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