Name _______________________________
CP Chemistry Conceptual
2nd QE review sheets
For the 2nd Marking Period Quarterly Exam you need to know
Use your textbook, review sheets and notebook to answer or fill in the blanks. Read everything!!
Chapter 3 Introduction to the Periodic Table
Dimitri Mendeleev (1834 -1907) produced the First Periodic Table when he listed the about 70 elements,
discovered at the time, in columns of elements with similar properties and increasing atomic masses. He had to
leave blank spaces and predicted that elements belong there which had not yet been discovered (he was right).
In 1913, Henry Moseley arranged elements by atomic numbers instead of atomic mass. This is how our
Modern Periodic Table is arranged today, with increasing atomic number from left to right and top to bottom.
Elements are also arranged so that elements in the same column have similar properties.
1) Word bank:
properties,
atomic #,
period,
group,
family,
main group, transition
elements,
inner transition elements,
left, upper right, lustrous,
malleable, ductile,
brittle,
gas, liquid or solid at room temp., good conductor (of electricity and heat),
insulator,
mercury Hg
In the Modern Periodic Table, elements are arranged in columns by similarities in their __________________.
The elements are listed left to right and then top to bottom by increasing _______________________________.
Horizontal rows are called ____________________ , vertical columns ______________ or _______________.
Each group (column) is identified either
by a number (1-18),
or by letter A or B and a roman numerals (I – VIII) or arabic number (1-8)
Letter A elements are called _______________________________ elements (long columns).
Letter B elements are ______________________________ and _____________________________________.
Metals make up 80% of all elements. They are found on the _______________ side of the Periodic Table.
Properties of metals:
__________________________________________________________________________________________
solid at room temperature except one (…………………….)
Nonmetals are found in the _________________________________ corner of the Periodic Table.
Properties of nonmetals:
__________________________________________________________________________________________
2) Identify each of the following sets of elements by their numbered location on the periodic table on the right.
Some of the sets are made up of a combination of several numbered areas!
a. Main group elements _______
b. inner transition elements ______ (lanthanides and actinides)
c. nonmetals _________
d. transition metals ________ e. metals ______
1
Name _______________________________
2nd QE review sheets
CP Chemistry Conceptual
3) Determine for the following elements if it is
a) a nonmetal
b) transition metal
c) lanthanide
d) noble gas
e) main group metal
Cl___
P___
Al___
H___
Ce___
Ca___
Xe___
Cu___
Ti___
Chapter 4 Formation of Compounds
Valence Electrons
• are the electrons in the outermost occupied energy level.
• The maximum number of valence electrons is 8.
• The number of valence electrons for A-groups in the periodic table is
equal to the A-group number
(1A = 1, 2A = 2, 3A = 3, 4A = 4, 5A =5, 6A = 6, 7A = 7, 8A = 8)
• Valence electrons are the ones interacting with other atoms, thus being
responsible for many properties and the chemical reactivity of the
atoms.
Lewis Electron Dot Structures show valence electrons as dots around the four sides of the element’s symbol.
Your turn: Determine the number of valence electrons for each atom and draw the electron dot diagram
Cl
H
Al
Ca
Xe
P
S
As
Elements are made from one type of atoms
Compounds are substances composed of two or more different elements chemically combined. Compounds
can be separated into simpler substances only by chemical means. Their properties differ greatly from the
properties of the original elements (e.g. Na and Cl2 very different from NaCl). There are ionic compounds and
molecular compounds.
Noble Gas elements are extremely stable or unreactive (inert gases).
Octet Rule. Atoms become stable (like noble gases) by reacting to achieve the same number of valence
electrons as a noble gas (Group 18), usually eight (8) valence electrons (exception Helium = 2).
Ionic compounds
One way to achieve a stable electron structure is to transfer electrons
from one atom to another, thus forming charged ions of opposite
charge. The ions attract each other to form a crystal lattice. Ionic
compounds are electrically neutral, because the total positive charge
of the cations is equal to the total negative charge of the anions.
Ionic compounds are usually formed from metal + nonmetals and are
brittle, crystalline solids at room temperature. When melted or in
aqueous solution, ionic compounds can conduct electricity =
Electrolytes.
Chloride
anion
18 e17 p+
18 no
10 e11 p+
12 no
Sodium
cation
Arrangement
of Na+ and Clions in crystals
of NaCl
Crystals of
sodium chloride
Ions
Cations ⇒Metallic elements tend to lose electrons and form cations (with a positive charge)
Anions ⇒Nonmetallic elements tend to gain electrons and form anions (with a negative charge) [A Negative ION]
1) Complete table. Choosing from positive/negative charge, losing/gaining electrons, metals/nonmetals
Ion
cation
anion
Atoms or groups of
Positive or negative
atoms that have a…
charge
Formed by
Losing or gaining
electrons
Which elements?
Metals and nonmetals
2
Name _______________________________
2nd QE review sheets
CP Chemistry Conceptual
Molecular compounds
are made from all nonmetals in molecules. Nonmetal
atoms achieve their octet here by sharing electrons,
forming covalent bonds. One shared pair of valence
electrons constitutes a single covalent bond. .
Sometimes two or three pairs of electrons may be shared to give double or triple covalent bonds
In a stable molecule each single electron (single dot) has to be shared with a single dot from another nonmetal
atom, and the total number of valence electrons for each atom including shared electrons is 8 (except hydrogen 2).
A Molecular Formula shows the kinds and numbers of atoms present in a molecule, the chemical formula of a
molecular compound.
A Formula Unit is the lowest whole-number ratio of ions in an ionic compound, the chemical formula of an ionic
compound.
Comparing Ionic and Molecular Compounds
Characteristics
Molecular Compound
Ionic Compound
From element types
All nonmetals
Metal and nonmetals
Composed of
Molecules
Ions
Formed by____ electrons
Sharing
Gaining and losing
Type of bonds
Covalent
Ionic
Melting points usually
low
high
Physical state at room temp.
Can be solid, liquid or gas
Solid, brittle crystalline
Only when melted or dissolved
Conducts electricity
Usually not (except acids)
in water (electrolytes)
3. Assign: a) anions or c) cations
After losing electrons _________
Metals form ________ positive charge ________
after gaining electrons ______
nonmetals form _________ negative charge ________
4. Circle those elements that are metals:
K
S
C
Mg
H
Se
Na
Ti
Fe
O
Cl
5. Would the following pairs of atoms combine chemically to give ionic ( i ) or molecular (m) compounds?
(metal + nonmetal or all nonmetals)
a) Sr and S
_______
6. Assign:
a) Molecular compound (molecular formula)
CNH5 ___
b) Cl and F ______
NaCl ____ MgCl2 ____
CO2 ____
c) Se and F ______
or
d) Al and Br _______
b) ionic compound (formula unit)
H2O _____ TiO2 ____ BaF2 _____
SO3 _____
7. Determine if the following statements refer to ionic compounds (i) or molecular compounds (m)
____ metal + nonmetal
____ all nonmetals
____ ions (anions and cations) ____ionic bonds
____ covalent bonds
____molecules
____ electrolytes
____ brittle solid crystals
____gaining and losing electrons ____ sharing electrons ____ can be solid or liquid or gas at room temperature
____ LiCl
_____ H2O2
____ NO2
_____ BaO
_____CO?
_____ CH3OH
3
Name _______________________________
8) Word bank: molecular compound
binary compound
ternary compound
2nd QE review sheets
CP Chemistry Conceptual
formula unit
ionic compound
cation
molecular formula
octet rule
polyatomic ion
__________________________ Atoms become stable by having eight electrons in their outermost energy level.
__________________________ Compound composed of two different elements.
__________________________ Compound composed of three or more different elements.
__________________________ Compound composed of all nonmetals.
__________________________ Compound composed of ions, usually metals with nonmetals.
__________________________ The lowest whole-number ratio of ions in an ionic compound.
__________________________ The chemical formula of a molecular compound, representing one molecule.
__________________________ A metal atom after it lost an electron.
__________________________ A tightly bound group of atoms that behave as a unit and carries a charge.
9) Word bank: allotropes
alloy
electrolyte
crystal
hydrate
hygroscopic
__________________________ An ionic compound, that has a specific ratio of water molecules chemically
bonded (e.g. CuSO4 • 2 H2O).
__________________________ A substance that absorbs water molecules from the air.
__________________________ Different structural forms of one element resulting in different properties
(e.g. Carbon exists as diamond, graphite etc.).
__________________________ A regular repeating arrangement of atoms, ions, or molecules in 3 dimensions.
__________________________ A compound that conducts electricity when melted or dissolved in water.
__________________________ A solid homogenous mixture of metals.
Chapter 5 Chemical Names and Formulas of Compounds
!!! When writing names or formulas of compounds, first determine if the compound is molecular or ionic!!!
!!! For ionic compounds determine if they are binary or ternary!!!
Names and Formulas of Ionic Compounds
1)
assign the cation (positive +, first) and anion (negative -, second)
2)
Writing formulas:
a) criss-cross and
b) adjust subscripts to smallest whole # ratio
example: MgCl2 is correct, but Si2O4 must be divided by two, to SiO2
c) contains polyatomic ion: don’t change polyatomic ion; put it into parenthesis if more than one unit is needed. Example:
Mg2+ and NO3- combine to Mg(NO3)2
4
Name _______________________________
2nd QE review sheets
CP Chemistry Conceptual
The subscripts inside the polyatomic ion are not to be changed, canceled or divided (only look for smallest whole number
ratio outside of parenthesis.
Example: Mg2(SO4)2 will be changed to MgSO4 (2’s are canceled but not the 4)
3)
Writing names:
a) Metal or cation first, nonmetal or anion second
b) Metals (cations) keep the element’s name Mg2+
magnesium
c) Metals “that can vary” (from group 4A or B groups) need roman numeral after the cation’s name to indicate it’s charge.
Example: Fe2+ and NO3- combine to Fe(NO3)2 iron (II) nitrate
d) Monoatomic anions change ending to –ide
Example: Cl- chloride and MgCl2 magnesium chloride
e) Contains polyatomic ion: Polyatomic ions keep their name (look up in table below, given on the exam)
Example: Mg(NO3)2 is magnesium nitrate, NH4Cl ammonium chloride
Some Polyatomic Ions (given on the exam)
Formula
NH4+
CO32
SO4
PO4
Name
ammonium
-
carbonate
2-
Formula
NO3
OH
phosphate
hydroxide
-
sulfate
3-
Name
nitrate
Cyanide
CN
-
Acetate
CH3COO
1). What is the charge of ions in the following groups of the periodic table? [0, -1, -2, -3, +1, +2, +3, or varies]
IA
Charge
IIA
IIIA
IVA
VA
VIA
VIIA
VIIIA
I-VIII B
+3
(Hydrogen as a nonmetal –1[hydride], in acids +1)
2) What is the charge of the ions formed from the following main group elements?
P ____, Cl ____, K____, S _____, Ca____, Mg____, H____, Ne _____, Na ____, O____, Al___
3) Write the correct formula (Criss cross and check for lowest whole# ratio)
Ca2+ and Br − ⇒
K+ and O2−
Cr3+ and S2− ⇒
Fe3+ and P3− ⇒
⇒
4) Write the names (underlined need roman numerals!) a) NaF _____________________________
b) FeSO4 _____________________________
c) MgBr2 _____________________________
d) CoO _____________________________
e) CaCO3 ____________________________
5) Write the correct formula and name (roman numeral for groups B and 4A) of ionic compounds made
from the following ions: (Polyatomic ions on page 11)
a) Cu+ S2Example Cu2S_________
b) Fe2+ Br- _________________________
___copper (I) sulfide________________
____________________________________
5
Name _______________________________
2nd QE review sheets
CP Chemistry Conceptual
c) Ca2+ OH- ____________________
d) Sr2+ CN- _________________________
_________________________________
____________________________________
e) Ni2+ PO43-
____________________
f) Co2+ F- _________________________
_________________________________
____________________________________
6) Find charges for both ions first, then write correct formula and correct name
+ 3-
a) Na P
__Example_Na3P______
b) Ba Br ___________________________
_____sodium phosphide_______________
____________________________________
c) Li
d) Al
N
____________________
_________________________________
Se _________________________
____________________________________
7) What is the charge of the ions in a) SnCl2
b) SnCl4
8) What is the formula for (check for charges and look up polyatomic ions in table)
a) calcium phosphide? _______________________
b) iron (III) oxide _______________________
c) chromium (III) hydroxide _______________________ d) strontium bromide _______________________
e) sodium hydroxide _______________________
f) lithium iodide _________________________
Binary Inorganic Molecular Compounds are named with prefixes and the ending –ide.
“Mono”
is not used for the first element Example: carbon dioxide CO2 Remember, the molecular formula represents the
# of atoms in one molecule, and not necessarily the lowest whole number ratio!
Prefixes: 1 = mono, 2 = di, 3 = tri, 4 = tetra, 5 = penta, 6 = hexa, 7 = hepta, 8 = octa, 9 = nona, 10 = deca
11) Write the formula of the following molecular compounds
silicon tetrafluoride __________________________
oxygen difluoride______________________________
carbon tetrachloride___________________________
diarsenic pentaoxide ___________________________
carbon monoxide ____________________________
carbon dioxide ________________________________
12) Write the name of the following molecular compounds
CS2 ______________________________________
AsBr5______________________________________
SO3 ______________________________________
N2O3 ______________________________________
6
Name _______________________________
2nd QE review sheets
CP Chemistry Conceptual
N2Cl4______________________________________
P2O5 _______________________________________
13) How many covalent bonds do you expect the following nonmetallic elements want, to achieve noble gas
configuration? Draw the electron dot diagram and count the single (unpaired) electrons or dots
H
C
Electron dot structures:
H•
Cl
N
S
Te
F
Kr
# of covalent bonds
1
14) Draw the electron dot structures for these molecular substances by sharing electrons (connecting single dots)
a) N2
b) COH4
c) AsH3
d) N2Cl4
H2
O2
C2F4
CNH3
CO2
C3H6
1) Diatomic molecules
Most elements are composed of single atoms (chemical formula =
chemical symbol of that element, e.g. iron = Fe, aluminum = Al,
sulfur = S etc.), but 7 exist as diatomic molecules: (formula H2
etc.)
They are ______________________________________________
Start at 7, make a 7 (+ hydrogen)
7
Name _______________________________
CP Chemistry Conceptual
2nd QE review sheets
Chapter 6 Chemical Reactions
In chemical reactions reactants are converted to products. Bonds, holding atoms together, are broken and new
bonds are formed. Atoms are neither created nor destroyed, just rearranged. “Law of conservation of matter”
Reactants → Products.
Carbon + oxygen → carbon dioxide
Word Equation
4 Fe + 3 O2
→ 2 Fe2O3
Balanced Equation gives the correct ratio of reactants and products
On each side of the equation must be the same number of atoms for each element.
Coefficients are the numbers written before the chemical formulas in a balanced equation.
!!!Never change subscripts or write numbers inside a formula when balancing equations.!!!
There are five basic types of reactions:
1. In a synthesis reaction, two or more substances combine to form a single product
A + B + … → AB..
Examples:
Fe (s) + S(s) → FeS (s)
iron (II) sulfide
CaO(s) + H2O (l) → Ca(OH)2 (aq)
calcium hydroxide
Reactants: Generally two elements, or two compounds with at least one being a molecular compound).
Probable Products:
A single compound
2. In a decomposition reaction, a single reactant is broken down into two or more products
AB.. → A + B + ...
Examples:
CaCO3 (s) → CaO (s) + CO2 (g)
dynamite explosion
(“opposite of combination reaction)
Reactants:
Generally a single binary or ternary compound
Probable Products:
two or more elements and/or compounds.
3. In a single-replacement reaction, one element replaces a second element in a compound
AB + C → AC + B
Example:
Mg (s) + 2 AgNO3 (aq) → Mg(NO3)2 (aq) + 2 Ag (s)
One metal can displace another metal or hydrogen from another compound.
Reactants: An element and a compound. One element replaces a second element in a compound.
Probable Products:
A different element and a new compound.
You don’t need to know the order of reactivity in single replacement reactions for the midterm.
4. Double-replacement reactions involve an exchange of positive ions between two reacting compounds
Reaction is driven by formation of a precipitate (solid), gaseous product, or water.
AB + CD → AD + CB
Example:
NaS (aq) + Cd(NO3)2 (aq) → CdS (s) + 2 NaNO3 (aq)
Reactants:
Generally a reaction between two ionic compounds.
Probable Products:
Two new ionic compounds, on being solid, gaseous or water.
5. In a combustion reaction an element or compound reacts rapidly with oxygen to form one or more oxides,
releasing energy usually in form of heat or light.
CxHy + O2 → CO2 + H2O
Example:
2 C2H6(g) + 7 O2(g) → 4 CO2(g) + 6 H2O(g)
Reactants:
Oxygen and a compound composed of mainly C and H.
Probable Products:
CO2 and H2O (complete combustion). Without sufficient oxygen, carbon monoxide
and carbon (soot) may also be formed (incomplete combustion).
8
Name _______________________________
2nd QE review sheets
CP Chemistry Conceptual
A catalyst is a substance that speeds up the rate of a reaction but is not used up in the reaction. Because its
neither reactant nor product it is written above the arrow.
1) Explain the following symbols that are used in these two chemical equations:
∆
Pt
AgNO3 (aq) + Fe (s) → Fe(NO3)3 (aq) + Ag (s)
H2 (g) + O2 (g) →
H2O (l)
(aq)
______________________________________________
(s)_______________________________
(g)
______________________________________________
(l)_______________________________
Pt written over the arrow ______________________________________________________________
(other formulas are possible)
∆ written over the arrow ______________________________________________________________
2) Word bank: law of conservation of matter
single replacement
product
endothermic
combustion reaction
decomposition
reactant
exothermic
synthesis reaction
double replacement
coefficient
catalyst
__________________________ A new substance formed in a chemical reaction (on the right).
__________________________ A substance that is undergoing a chemical reaction (on the left).
__________________________ Chemical reaction that gives off energy.
__________________________ Chemical reaction that absorbs energy.
__________________________ Atoms are neither created nor destroyed just rearranged (matter is conserved).
__________________________ A number placed in front of the chemical formulas in a balanced chemical
equation to indicate how many are involved.
__________________________ Chemical reaction with only one product.
__________________________ Chemical reaction with only one reactant.
__________________________ Rapid exothermic reaction with oxygen, forming CO2 and H2O.
__________________________ Two ionic compounds switching ions.
__________________________ One element replaces another element in a compound.
__________________________ a substance that speeds up the rate of a reaction without being used up
3) Word bank (6.3): (use numbers) 1) activation energy 2) collide 3) catalyst 4) temperature 5) concentration
In a chemical reaction the particles involved must _____with enough force to initiate the chemical change.
The energy needed for a reaction to occur is called _____ of the reaction. The rate of a reaction can often be
increased by increasing ____ or _____, or by adding a ____.
9
Name _______________________________
4) Word bank
2nd QE review sheets
CP Chemistry Conceptual
a) reversible reaction
g) dynamic equilibrium
b) inhibitor
h) reaction rate
f) activation energy
____ 1) a substance that slows down the rate of a reaction
____ 2) a reaction that can change direction
____ 3) reactants and products are formed at the same time and at the same rate (speed)
____ 4) changing temperature, concentration, or adding a catalyst or inhibitor are ways to change the
____ 5) The energy needed for a reaction to occur
5) a) In the diagram, label reactants, products and activation energy.
b) into the same diagram, draw a second curve representing the same reaction after a catalyst had been added
c) into the same diagram, draw a third curve representing the same reaction after an inhibitor had been added
6) in the empty box to the right draw a diagram representing an endothermic reaction.
6)
5)
7) Types of Reactions
Match the generic reaction type with its correct name
_____
A+B
→
AB
_____
AB
→
A+B
_____
A + BC
→
B + AC
c. double replacement reaction
_____
AB + CD
→
AD + CB
d. single replacement reaction
_____
CxHy + O2
→
CO2 + H2O
e. decomposition reaction
a. combustion reaction
b. synthesis reaction
10
Name _______________________________
CP Chemistry Conceptual
2nd QE review sheets
8) Balance the following reactions
and indicate which
type of reaction they are.
a) _____Al2O3 + _____ Li →
____ Al + ____ Li2O
Type:_____________________
b)
___Ti_ + ____ Cl2
c) _____Mg + _____HCl
→ _____ TiCl4
→
_____ MgCl2
Type:_____________________
+ _____H2
d) _____NaOH + _____ H2SO4 → _____ H2O +_____ Na2SO4
Type:_____________________
Type:_____________________
11
Name _______________________________
e) _____S
f)
+
_______O2 →
CP Chemistry Conceptual
_____ SO3
_____C7H14 + _____O2 → ______ CO2 + _____ H2O
g) _______HgO
→ _______Hg + ________O2
h) _____ NaCl + _____Fe(NO3)3 → _____FeCl3 + _____ NaNO3
2nd QE review sheets
Type:_____________________
Type:_____________________
Type:_____________________
Type:_____________________
For the exam you are allowed to use a calculator. You also receive a periodic table, a metric unit prefix
conversion sheet (see page 3), and lists of polyatomic ions and of prefixes for molecular compounds.
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