CHAPTER 3
STOICHIOMETRY
Atomic Masses and the Mass Spectrometer
23.
Average atomic mass = A = 0.0800(45.95269) + 0.0730(46.951764) + 0.7380(47.947947)
+ 0.0550(48.947841) + 0.0540(49.944792) = 47.88 a
CHAPTER 2
ATOMS, MOLECULES, AND IONS
Development of the Atomic Theory
18.
Law of conservation of mass: mass is neither created nor destroyed. The total mass before a
chemical reaction always equals th
CHAPTER 7
ACIDS AND BASES
Nature of Acids and Bases
16.
NH3 + NH3
Acid
Base
NH2
+ NH4+
Conjugate Conjugate
Base
Acid
One of the NH3 molecules acts as a base and accepts a proton to form NH4+ . The oth
CHAPTER 6
CHEMICAL EQUILIBRIUM
Characteristics of Chemical Equilibrium
10.
a. This experiment starts with only H2 and N2, and no NH3 present. From the initial mixture diagram, there is three times as
CHAPTER 5
GASES
Pressure
21.
4.75 cm
10 mm
1 atm
= 47.5 mm Hg or 47.5 torr; 47.5 torr
= 6.25 102 atm
cm
760 torr
6.25 102 atm
22.
1.013 10 5 Pa
= 6.33 103 Pa
atm
If the levels of mercury in each ar
CHAPTER 4
TYPES OF CHEMICAL REACTIONS AND SOLUTION
STOICHIOMETRY
Aqueous Solutions: Strong and Weak Electrolytes
10.
The electrolyte designation refers to how completely the dissolved solute breaks up
CHAPTER 8
APPLICATIONS OF AQUEOUS EQUILIBRIA
Buffers
15.
A buffer solution is one that resists a change in its pH when either hydroxide ions or protons
(H+) are added. Any solution that contains a wea
CHAPTER 10
SPONTANEITY, ENTROPY, AND FREE ENERGY
Spontaneity and Entropy
12.
a. A spontaneous process is one that occurs without any outside intervention.
b. Entropy is how energy is distributed among
CHAPTER 11
ELECTROCHEMISTRY
Galvanic Cells, Cell Potentials, and Standard Reduction Potentials
15.
Electrochemistry is the study of the interchange of chemical and electrical energy. A redox
(oxidatio
CHAPTER 9
ENERGY, ENTHALPY, AND THERMOCHEMISTRY
The Nature of Energy
15.
Ball A: PE = mgz = 2.00 kg
196 kg m 2
9.81 m
10.0 m =
= 196 J
s2
s2
At point I: All this energy is transferred to ball B. All
Periodic Table of the Elements
1
1
2
H
H
He
1.00794
4.002602
1.00794
3
4
5
6
7
8
9
10
Li
Be
B
C
N
O
F
Ne
6.941
9.012182
10.811
12.0107
13
14
15
16
17
18
Al
Si
P
S
32.066
Cl
Ar
35.4527
39.948
32
33
34
USA
AMC 12/AHSME
2000
1 In the year 2001, the United States will host the International Mathematical Olympiad. Let
I, M , and O be distinct positive integers such that the product I M O = 2001. Whats
2006 AMC 8
AMC 8 2006
1
Mindy made three purchases for $1.98, $5.04 and $9.89. What was her total,
to the nearest dollar?
(A) $10
(B) $15
(C) $16
(D) $17
(E) $18
2
On the AMC 8 contest Billy answers 1
2014 AMC 8
AMC 8 2014
1
Harry and Terry are each told to calculate 8 (2 + 5). Harry gets the correct
answer. Terry ignores the parentheses and calculates 82+5. If Harrys answer
is H and Terrys answer
2013 AMC 8
AMC 8 2013
1
Danica wants to arrange her model cars in rows with exactly 6 cars in each
row. She now has 23 model cars. What is the smallest number of additional
cars she must buy in order
2007 AMC 8
AMC 8 2007
1
Theresas parents have agreed to buy her tickets to see her favorite band if she
spends an average of 10 hours per week helping around the house for 6 weeks.
For the rst 5 weeks
2009 AMC 8
AMC 8 2009
1
Bridget bought a bag of apples at the grocery store. She gave half of the apples
to Ann. Then she gave Cassie 3 apples, keeping 4 apples for herself. How many
apples did Bridge
2012 AMC 8
AMC 8 2012
1
Rachelle uses 3 pounds of meat to make 8 hamburgers for her family. How
many pounds of meat does she need to make 24 hamburgers for a neighborhood
picnic?
2
1
(A) 6
(B) 6
(C) 7
2008 AMC 8
AMC 8 2008
1
Susan had $50 to spend at the carnival. She spent $12 on food and twice as
much on rides. How many dollars did she have left to spend?
(A) 12
2
(B) 14
(B) 8672
(D) 9782
(E) 987
2011 IMO Shortlist
IMO Shortlist 2011
Algebra
1
Given any set A = cfw_a1 , a2 , a3 , a4 of four distinct positive integers, we denote
the sum a1 + a2 + a3 + a4 by sA . Let nA denote the number of pai
2013 IMO Shortlist
IMO Shortlist 2013
Algebra
A1
Let n be a positive integer and let a1 , . . . , an1 be arbitrary real numbers. Dene
the sequences u0 , . . . , un and v0 , . . . , vn inductively by u
2012 IMO Shortlist
IMO Shortlist 2012
Algebra
A1
Find all functions f : Z Z such that, for all integers a, b, c that satisfy
a + b + c = 0, the following equality holds:
f (a)2 + f (b)2 + f (c)2 = 2f
2010 IMO Shortlist
IMO Shortlist 2010
Algebra
1
Find all function f : R R such that for all x, y R the following equality
holds
f (x y) = f (x) f (y)
where a is greatest integer not greater than a.
Pr
2009 IMO Shortlist
IMO Shortlist 2009
Algebra
1
Find the largest possible integer k, such that the following statement is true:
Let 2009 arbitrary non-degenerated triangles be given. In every triangle
1998 IMO Shortlist
IMO Shortlist 1998
Geometry
1
A convex quadrilateral ABCD has perpendicular diagonals. The perpendicular
bisectors of the sides AB and CD meet at a unique point P inside ABCD.
Prove
2008 IMO Shortlist
IMO Shortlist 2008
Algebra
1
Find all functions f : (0, ) (0, ) (so f is a function from the positive real
numbers) such that
w 2 + x2
(f (w)2 + (f (x)2
= 2
f (y 2 ) + f (z 2 )
y +
2005 IMO Shortlist
IMO Shortlist 2005
Algebra
1
Find all pairs of integers a, b for which there exists a polynomial P (x) Z[X]
such that product (x2 + ax + b) P (x) is a polynomial of a form
xn + cn1
2002 IMO Shortlist
IMO Shortlist 2002
Geometry
1
Let B be a point on a circle S1 , and let A be a point distinct from B on the
tangent at B to S1 . Let C be a point not on S1 such that the line segmen
2001 IMO Shortlist
IMO Shortlist 2001
Geometry
1
Let A1 be the center of the square inscribed in acute triangle ABC with two
vertices of the square on side BC. Thus one of the two remaining vertices o
1996 IMO Shortlist
IMO Shortlist 1996
Algebra
1
Suppose that a, b, c > 0 such that abc = 1. Prove that
ab
bc
ca
+
+
1.
ab + a5 + b5 bc + b5 + c5 ca + c5 + a5
2
Let a1 a2 . . . an be real numbers such