Download Review Sheet for Chemistry* First Semester Final

Review Sheet for Chemistry* First Semester Final
Refer to your class notes, worksheets, and the textbook to complete this review sheet. Study early so that
you will have time to ask questions about what you don’t understand.
(* The study of matter and the changes it undergoes)
Matter: Anything that takes up space and has mass
 Physical Changes and Chemical Changes
Define each. How can you tell the difference between the two?
Classify the following as physical or chemical changes:
a. spoiling of milk ___________________
b. bending wire _____________________
c. cutting paper _____________________
d. rusting of a nail ___________________
 Put the following into a graphic organizer/flowchart and define each:
 Matter
 Pure substances – elements and compounds
 Mixtures – homogeneous (solutions) and heterogeneous
Identify the following as pure substances, homogeneous mixtures or heterogeneous mixtures:
a. copper ______________________
b. sweetened tea ________________
c. sand and water _______________
d. calcium carbonate (CaCO3) ________________________
 Sketch particles in the three states of matter. How close are the particles and how much do they move?
Solid
Liquid
Gas
Atom
 For this Carbon–14 isotope, 146 C
 Atomic number = _____, Mass number = _____,
 # of protons = _____, # of electrons = _____, # of neutrons = _____.
 Atomic Masses: What is the difference between the mass number for Carbon–14 and carbon’s atomic
mass of 12.011 amu?
 Calculate the atomic mass of lithium is one isotope has a mass of 6.0151 amu and a percent abundance of
7.59% and a second isotope has a mass of 7.0600 amu and a percent abundance of 92.41%.
 Atomic Models:
Philosophers: Democritus (believed in atoms) and Aristotle (didn’t believe in atoms)
Scientists: What was the contribution of each one’s atomic model? Draw a model of each.
 John Dalton
List the four postulates of Dalton’s Atomic Theory:
 J.J. Thompson

Earnest Rutherford

Niels Bohr

Quantum mechanical model (Werner Heisenberg):
 Energy levels (n=1, 2, 3, 4,…) – represented by periods on the periodic table
 Sublevels: (s, p, d, f) – represented by blocks on the periodic table
 Orbitals – region of space where up to 2 electrons may be found
 Electron Configurations. What element has the configuration [Ne]3s23p1? _____
 What does the 3 mean in 3s2 ?

What does the s mean?

What does the 2 mean?

How many valence electrons will an atom of this element have?

How many electrons will an atom of this element lose to form an ion? Why?

Write out the electron distribution according to Hund’s rule. The 1s2 sublevel is done for you.
1s2_↑ ↓___
2s2 ____
2p6 ____ ____ ____
3s2 ____
3p6 ____ ____ ____
 Emission (or bright-line) Spectrums
 What is needed for an electron to “jump” to a higher energy level?
 What happens when an “excited” electron falls back to its ground state?
 What does an emission spectrum allow one to do?
 Characteristics of subatomic particles
Particle
Mass
Charge
Location in atom
Proton
Neutron
Electron
Periodic trends
 Locate or define parts of the periodic table:
 Groups

Periods

Transition metals (d & f blocks) vs. Representative Elements (s & p blocks)

Alkali metals, Alkaline Earth metals, Halogens, Noble Gases
 Periodic Trends: Increasing or Decreasing from top to bottom or left to right?
Top to Bottom in a Group
Left to Right across a Period
electronegativity
ionization energy
atomic size
 Elements in the same ___________ have similar physical and chemical characteristics because the
(group, period)
they have the same number of _____________________.
(atoms, protons, neutrons, electrons, valence electrons)
 Draw a electron dot diagram (or Lewis Dot structure) for Be and for N
of valence electrons
showing the correct number
 From their positions on the periodic table, what charges would the ions of Be and N have?
Gains or loses electrons?
Symbol for ion
Gains or loses electrons?
Be
N
 Properties of Metals vs. Nonmetals vs. Metalloids
Metals
Luster?
Nonmetals
Symbol for ion
Metalloids
Malleable vs. Brittle
Conducts electricity &
heat?
Typical state(s) at
room temperature
Ionic vs. Molecular Compounds:
Ionic bonds are formed when a ____________ and a _________________ combine.
Metals lose electrons and form _____________ while nonmetals gain and electrons form __________.
Molecular compounds form when a ______________ and a _______________ combine as they share
electrons.
Identify the following pairs of atoms as potentially forming an ionic or molecular compound:
Mg and Cl ____________
I and F _________________ P and Cl _______________
Ag and S _____________
K and Br ________________ Sn and O _______________
Naming Molecular and Ionic Compounds

Naming molecular compounds
 Name: N2O: ___________________________ and NO2 ____________________________


Naming Ionic Compounds
Name: Li2O ___________________________ and (NH4)2SO4 __________________________

Name: FeO __________________________ and Sn3(PO4)4 ___________________________

Name: NaHCO3 ______________________ and CuCl2 _______________________________
Formulas of Molecular and Ionic Compounds

Write formulas for the following molecular compounds:
Water _____________________________________ silicon dioxide _________________________
Phosphorous trihydride _______________________ dioxygen difluoride _____________________
Lead (II) hydroxide __________________________ chromium (III) sulfate ___________________

Ba2+ with OH– ___________ iron (III) sulfide _________________
Write formulas for:
Na+ with OH– ___________ NH4+ with PO43– ______________ magnesium oxide____________
Chemical Reactions
 Define what is meant by the term chemical reaction.
 In the following chemical equation, identify the reactants and the products.
3Ba(C2H3O2)2(aq) + 2Na3PO4(aq)  Ba3(PO4)2(s) + 6NaC2H3O2(aq)
 In the above chemical equation, what do the symbols (aq) and (s) stand for? What would the symbols
(l) and (g) stand for in a chemical equation?
 Chemical reactions can often be classified as one of five types. Write the general form for each type of
reaction.
 Direct Combination (or synthesis):
 Decomposition
 Single-Replacement
 Double-Replacement
 Combustion
 Using the five types of reactions listed above, classify AND balance the following equations:
___Na(s) + ___Br2(l)  ___NaBr(s)
______________________________________
heat
___CH4(g) + ___O2(g) 
___CO2(g) + ___H2O(g)
______________________________________
___K2CrO4(aq) + ___Ba(NO3)2(aq)  ___BaCrO4(s) + ___KNO3(aq) _____________________________
electric
___H2O(l) 
___H2(g) + ___O2(g
_______________________________________
current
___Al(s) + ___Fe2O3(s)  ___Al2O3(s) + ___Fe(s)
___H2(g) + O2(g)  ___H2O(l)
_______________________________________
_______________________________________
heat
___C8H18(l) + ___O2(g)  ___CO2(g) + ___H2O(g) _____________________________________
Predicting Products:
Using the activity series, will the following reactions occur?
2Al (s) + Fe2O3 (aq)  Al2O3 (aq) + 2Fe (s)
y or n __________________
Zn (s) + 2HNO3 (aq)  Zn(NO3)2 (aq) + H2 (g) y or n __________________
Pb (s) + MgO (aq)  PbO (aq) + Mg (s)
y or n _____________________
Predict the products of the following reactions. Using the solubility table, predict if there will be a
precipitate. If there is a precipitate, what is it?
Reaction
Products
AgNO3 (aq) + KCl (aq) 
(NH4)PO4 (aq) + CaCl2 (aq) 
NH4NO3 (aq) + NaCl (aq) 
The MOLE!
Molar Mass:
What is the definition of molar mass?
Calculate the molar mass of the following:
Na:
Precipitate (Y/N)
What is
Precipitate?
Fluorine gas:
Mg(OH)2:
Methane- CH4:
Mole Conversions:
1.
Find the volume of 2.00 moles of hydrogen sulfide, H2S at STP.
2. How many moles are there in 37.0 L of sulfur dioxide, SO2 at STP?
3. How many particles are there in 2.00 moles of acetylene, C2H2?
4. What is the mass of 5.00 moles of acetylene, C2H2?
5. How many moles are in 72.0 g of sodium chloride, NaCl?
6. How many particles are there in 3.00 L of carbon monoxide, CO at STP?
7. Find the number of molecules in 1.26 g of phosgene, CCl2O.
8. How many liters are in 128 g of nitrogen gas, N2?
9. Find the number of grams in 8.20 x 1024 formula units of KCl.
Stoichiometry Practice
Hydrogen sulfide, a foul-smelling gas, is found in nature in volcanic areas. The balanced chemical
equation for the burning of hydrogen sulfide is given below. Interpret this equation in terms of the
interaction of the following three relative quantities.
1. The coefficients in this balanced reaction can represent
a. Number of moles
b. Number of liters
c. Number of particles
d. All of the above
2 H2S (g) + 3O2 (g)  2SO2 (g) + 2 H2O (g)
2. How many moles of sulfur dioxide will be produced when 6 moles of oxygen react completely?
3. What is the mole to mole ratio of…
a. Dihydrogen sulfide to oxygen?
b. Oxygen to water?
c. Dihydrogen sulfide to sulfur dioxide?