Science 9- First Semester Exam Review 2014-2015
What will your exam consist of?
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100 multiple choice questions over course content & laboratory assignments
Problems on atomic structure, equation balancing, formula mass calculation, formula writing
ion formation and drawing structural formulas
Atomic structure
A) Subatomic particles
a. What are the atomic mass units for protons, neutrons, and electrons?
What does the atomic number represent?
b. What does the mass number represent?
c. What particles are in equal numbers in a neutral atom?
d. How is the number of protons determined?
e. How is the number of neutrons determined?
f. How is the number of electrons determined in a neutral atom?
g. What subatomic particles are located in the nucleus?
h. Complete the following diagrams and fill in the charts for each element. Use the periodic
table as a reference.
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C) The electron cloud
a. What determines the location of an electron in the electron cloud?
b. How many electrons can be found in the first energy level of an atom?
c. How many electrons can be found in the second energy level of an atom?
d. How can the electron arrangement/configuration be determined for a neutral atom?
D) Isotopes
a. How are isotopes different from other forms of the same element?
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b. Which pairs of atoms are isotopes of the same element?
i.
ii.
16
8O
and
122
50Sn
iii.
39
17Cl
iv.
121
50Sn
17
8O
and
and
122
52Te
39
19K
and
119
50Sn
c. Identify the most abundant isotope for each element.
i. Fe-54 Fe-56 Fe-57 Fe-58
ii. O-16 O-17 O-18
iii. Mg-24 Mg-25 Mg-26
iv. S-32 S-33 S-34 S-36
v. Ar-36 Ar-38 Ar-40
vi. Hg-196 Hg-198 Hg-199 Hg-202 Hg-204
vii. Kr-78 Kr-80 Kr-82 Kr-83 Kr-84 Kr-86
Periodic Table
A) Identifying elements by atomic number
a. Atomic # is the number of?
B) Identifying elements with the same number of valence electrons (which column?)
a. Which elements have one valence electron?
b. Which elements have two valence electrons?
c. Which elements have three valence electrons?
d. Which elements have four valence electrons?
e. Which elements have five valence electrons?
f. Which elements have six valence electrons?
g. Which elements have seven valence electrons?
h. Which elements have eight valence electrons?
C) Identifying elements by family
a. Which elements are alkali metals?
b. Which elements are alkaline earth metals?
c. Which elements are halogens?
d. Which elements are noble gases?
D) Identifying elements by period (which row?)
a. Which elements have one electron shell?
b. Which elements have two electron shells?
c. Which elements have three electron shells?
d. Which elements have four electron shells?
e. Which elements have five electron shells?
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f. Which elements have six electron shells?
g. Which elements have seven electron shells?
E) Identifying elements by area of the periodic table
a. Which elements are metals?
b. Which elements are nonmetals?
c. Which elements are metalloids?
d. Which elements are transition metals?
Using the Periodic Table, give the following information for the element Nitrogen:
_______________1. Number of protons
_______________2. Number of neutrons
_______________3. Number of valence electrons
_______________4. Number of electron shells
_______________5. Metal or non-metal?
_______________6. Symbol of the element with the next highest atomic number
_______________7. Name of the chemical family containing Nitrogen
_______________8. Name of another element in the same family with Nitrogen
_______________9. Name of another element in the same period with Nitrogen
Ionic bonding
A) Electrons are transferred between atoms
B) Valence electrons- outer shell electrons
C) Metals
a. Lend valence electrons
b. 1 – 4 valence electrons
c. Form positive ions ( cations-more protons than electrons)
D) Nonmetals
a. Borrow valence electrons
b. 4 - 8 valence electrons
c. Form negative ions (anions-more electrons than protons)
E) Metals lend and non-metals borrow to become stable.
a. Stable- having only full outer electron shells
F) Oxidation number
a. The number of electrons an atom can lend, borrow, or share
b. Metals have positive oxidation numbers
1. Calcium has two outer shell electrons
2. Calcium lends two electrons
3. Calcium has an oxidation number of 2+
c. Nonmetals have negative oxidation numbers
1. Oxygen has six outer shell electrons
2. Oxygen gains two electrons to have a full outer shell of 8
3. Oxygen has an oxidation number of 2d. There are no oxidation numbers above 4.
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G) Draw the electron configuration for the following:
a. Potassium
c. Aluminum
b. Lithium
d. Carbon
H) Draw the ionic bonds between the following. Make sure to draw the Lewis Dot structures. Which
ones are the anions and cations:
c. Sodium & Phosphorus
d.
Lithium & Chlorine
I) Draw the electron dot diagram and then tell if it would give up or take on electrons to get a full
shell. Also tell what charge it would have (positive or negative and how much ex: +2)
Mg
P
Cl
Br
Rules for formula writing
A) Metals are listed first
B) Nonmetals are listed second
C) The total number of electrons shown as being lost by the metal must equal the total number of
electrons shown being gained by the nonmetal.
D) The number 1 is NOT used as a subscript.
E) When the subscripts would be the same for both the metal and nonmetal they are not used.
F) Examples
a. Calcium and Chlorine- CaCl2
b. Magnesium and oxygen- MgO
c. Magnesium and phosphorus- Mg3P2
G) Write the formulas for the following compounds.
1. Magnesium chloride ______________________
2. Magnesium nitride _______________________
3. Copper (II) nitride _______________________
4.Titanium(III) oxide ______________________
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H) Write the correct formula for each of the following compounds.
1) Cesium fluoride (cesium & fluorine)
4) Strontium nitride (strontium & nitrogen)
2) Potassium oxide (potassium & oxygen)
5) Aluminum bromide (aluminum & bromine)
3) Rubidium nitride (rubidium & nitrogen)
6) Aluminum iodide (aluminum & iodine)
Types of chemical reactions
Synthesis
A+B
Decomposition
AB
AB
A+B
Single Replacement
Double Replacement
AB + C
AB + CD
CB + A
CB + AD
Tell what kind of reactions are the following (synthesis, decomposition, etc):
a. CaCl2 + Na2CO3  CaCO3 + 2NaCl ___________________________
b. HC2H3O2 + NaHCO3  NaC2H3O2 + H2O + CO2 ________________________
c. NaCl  Na + Cl2 __________________________
d. NaOH + HCl  H2O + NaCl _________________________
e. K + Cl2  KCl ____________________________
f. K + AgCl  Ag + KCl _____________________________
g. KOH + HNO3  H2O + KNO3 ______________________________
h. Al2(SO4)3 + Ca(OH)2  Al(OH)3 + CaSO4 _______________________________
i.
Na2O + CO2  Na2CO3 ____________________________________
j. Pb(NO3)2 + 2HCl  2PbCl2 + 2HNO3 __________________________
k. Ca + 2HCl  CaCl2 +H2 _____________________________
Components of a chemical reaction
A. Matter
a. Identify products in a chemical equation
b. Identify reactants in a chemical equation
c. Reactants
Products
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B. Energy
Exothermic reactions
 More energy is released than is
needed to continue the reaction
 Reactants have more
energy than products
 Energy is released to the
surroundings
 Would feel warm
Endothermic reactions
 Less energy is released than
is needed to continue the reaction
 Products have more
energy than reactants
 Energy is absorbed
from the surroundings
 Would feel cold
A) What types of reactions involve breaking of chemical bonds and heat being released?
____________________
B) The exothermic reaction has energy _________________ by the reaction.
C) The endothermic reaction has energy _______________________ by the reaction.
D) This reaction is cold to the touch. _____________________
E) This reaction is warm/hot to the touch. ___________________
Law of Conservation of Mass
A. In a chemical reaction mass is neither lost nor gained.
a. Atoms are rearranged
b. Equations are balanced to show Conservation of Mass
B. For the equation below, put a circle around the subscripts and a square around the coefficients.
2H2CO3 + 2NaOH  Na2CO3 + 2H2O
Reaction rate
A. Substances must collide to react
B. The more collisions the faster the reaction
C. Four factors that affect reaction rate
a. Surface area- amount of exposed surface
b. Temperature- affects how fast particles move
c. Catalysts- affect reactions without being part of the reaction
d. Concentration- how much of a material is in a given area
Phase Changes- On the diagram below label solid, liquid, gas, melting, evaporation, condensation, freezing.
(B and D have two answers) Label right on the diagram.
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Determine if the following is a chemical or physical change:
1. Oxygen is odorless and colorless
2. Copper turns green when exposed to the environment
3. The piece of metal is magnetic
4. The density of water is 1.0 gram per cubic centimeter
5. Diamonds are a very hard substance
6. The tree is 8 meters high
7. Sodium reacts very easily with other elements.
8. Copper conducts electricity
9. Nitrogen is a colorless gas
10. The silver spoons tarnished and turned dark
11. The piece of metal is magnetic
Measurements and lab equipment
There will be questions about proper lab equipment usage.
-remember to measure as accurately as the equipment allows and estimate one place further
-if using a digital scale and the mass is 31.00 g you must write out 31.00 not 31.0 or 31.
You need to be able to do density calculations.
-memorizing the pyramid with M over D/V may help
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