Test 1 Practice Problems
Fill in the blank for the phase changes below:
Describe the properties of each of
Solid __________________________ Gas
the states of matter.
Liquid __________________________ Solid
Gas
Solid:
__________________________ Solid
Liquid __________________________ Gas
Liquid:
Solid __________________________ Liquid
Gas
__________________________ Liquid
Gas:
Label each as a heterogeneous or homogeneous mixture.
Salt water
___________________________
Brewed tea/coffee
___________________________
Oil and water
___________________________
Dilute HCl solution
___________________________
Carbonated beverage ___________________________
Sandy water
___________________________
Blood
___________________________
Name three examples of pure substances.
1. _____________________________
2. _____________________________
3. _____________________________
Label each as a compound, a molecule, or an atom (put two if applicable).
H2O
_____________________________
Au
_____________________________
CO2
_____________________________
H2
_____________________________
Ne
_____________________________
Name all 7 diatomic molecules.
Name three physical properties and three chemical properties
Label each property below as intensive or extensive.
Density
____________________________
Color
____________________________
Mass
____________________________
Boiling point ____________________________
Volume
____________________________
Enthalpy
____________________________
Define physical and chemical changes providing one example of each.
Name the three methods of separation from lecture and what they separate (Ex.
homogeneous mixtures).
1. ______________________________________________
2. ______________________________________________
3. ______________________________________________
Convert the following temperatures:
32˚F  _________________˚C
42˚C  _________________K
376 K  _________________˚C
200 K  _________________˚F
Calculate the values for the density problems below:
Mass = 24.5 g
Volume = 4.67 mL
Density = 12.10 g/mL
Mass = 46.07 g
Density = ?
Volume = 2.3 mL
Density = 3.08 g/mL
Mass = ?
Volume = ?
Convert the following:
25 kilometers  ________________________ nanometers
3.74 millimeters  ________________________ gigameters
400 petagrams  __________________________ grams
0.078 femtometers  ________________________ millimeters
16.2 liters  ____________________________ microliters
Write the number of significant figures in each example below:
0.0032
_____________
1.0462
_____________
203
_____________
402,000
_____________
6,000.
_____________
0.000005
_____________
Reduce the following examples to the specified number of significant figures.
1.067 to 2 sig figs
________________________
670,000. to 2 sig figs ________________________
0.034 to 1 sig fig
________________________
22.3 to 2 sig figs
________________________
56.45 to 3 sig figs
________________________
7.35752 to 4 sig figs ________________________
Complete the following calculations with the correct number of significant figures.
20.42 – 18.3 + 2.36 = _________________________
5.78 x 11.4 x 3.2 =
_________________________
(4.31 + 6.88) / 2.5 = _________________________
12.02 x (7.0 – 4.33) = _________________________
Convert the following values using dimensional analysis.
17 miles  inches (5280 ft = 1 mi)
1200 m/s  km/hr
1 year  seconds
Complete the table below:
Protons
Neutrons
Electrons
Ne
Fe2+
37
Cl
35
Cl
O2Complete the following average atomic mass problems.
Rubidium is a soft, silvery-white metal that has two common isotopes, 85Rb and 87Rb. If
the abundance of 85Rb is 72.2% and the abundance of 87Rb is 27.8%, what is the average
atomic mass of rubidium?
Uranium is used in nuclear reactors and is a rare element on earth. Uranium has three
common isotopes. If the abundance of 234U is 0.01%, the abundance of 235U is 0.71%, and
the abundance of 238U is 99.28%, what is the average atomic mass of uranium?
Titanium has five common isotopes: 46Ti (8.0%), 47Ti (7.8%), 48Ti (73.4%),
49Ti (5.5%), 50 Ti (5.3%). What is the average atomic mass of titanium?
Label each of the following as ionic or molecular.
H2O
_______________________
NaCl _______________________
CO2
_______________________
Fe2O3 _______________________
C6H12O6 ______________________
Reduce the following molecular formulas to empirical formulas.
C6H12O6
___________________
C5H5
___________________
C2H6
___________________
Determine the charges of the following ions:
Cl
________________
O
________________
Na
________________
Ca
________________
N
________________
PO4
________________
Al
________________
Write the chemical formulas for the compounds made from the ions below:
Mg2+ + N3-  ______________________
Ca2+ + Cl-  ______________________
NH4+ + SO42- _____________________
Na+ + Cl- 
______________________
Al3+ + O2-  ______________________
Fe2+ + O2-  ______________________
Write the two ions that compose each of the following compounds:
Mg(OH)2
______________________
CaCO3
______________________
Li2O
______________________
Name the following compounds, or write the formula from the given name:
Sodium chloride
_________________________
KOH
_________________________
CaCO3
_________________________
Fe2O3
_________________________
Calcium sulfite
_________________________
CO2
__________________________
Mg3N2
__________________________
Carbon tetrachloride __________________________
CuSO4
__________________________
CO
__________________________
Dinitrogen pentoxide __________________________
HBr
__________________________
Ammonium chloride __________________________
Iron (II) oxide
__________________________
Pb(NO3)2
______________________________
Ba(OH)2
______________________________
Sodium sulfate
______________________________
(NH4)3PO4
______________________________
Lithium carbonate
______________________________
Iron (II) oxide
______________________________
Balance the following reactions.
_____CH4 + _____O2  _____CO2 + _____H2O
_____Ca + _____N2  _____Ca3N2
_____NH3  _____N2 + _____H2
_____Al + _____O2  _____Al2O3
_____Na + _____H2O  _____NaOH + _____H2
_____NaHCO3  _____Na2CO3 + _____CO2 + _____H2O
_____KIO3  _____KI + _____O2
_____Fe + _____O2  _____Fe2O3
_____Fe2O3 + _____Al  _____Al2O3 + _____Fe
_____P4 + _____Cl2  _____PCl3
_____H2 + _____O2  _____H2O
_____P4 + _____O2  _____P2O5
_____P2O5 + _____H2O  _____H3PO4
_____NaH + _____BF3  _____B2H6 + _____NaF
_____Fe3O4 + _____CO  _____Fe + _____CO2
Classify the following reactions as combination, decomposition, or combustion reactions.
2H2O2  2H2O + O2
__________________________________
2Na + Cl2  2NaCl
__________________________________
Mg + F2  MgF2
__________________________________
2C2H6 + 7O2  4CO2 + 6H2O
__________________________________
2NI3  N2 + 3I2
__________________________________
2C8H18 + 25O2  16CO2 + 18H2O __________________________________
Write the balanced chemical reaction for the following examples.
Methanol (CH3OH) burns in excess oxygen gas.
Solid sodium is added to iodine vapor.
Magnesium metal is burned in oxygen gas.
Molten aluminum chloride is electrolyzed (decomposed).
Solid calcium carbonate is heated to decomposition.
Propane (C3H8) combusts in air.
Find the formula/molecular weight of the following compounds.
LiF
__________________________
CaCO3
__________________________
Na2SO4
__________________________
NH4NO3
__________________________
C6H12O6
__________________________
C2H5OH
__________________________
HClO3
__________________________
Sr(OH)2
__________________________
Find the percent composition of each of the elements in the following compounds.
NaCl
Na: __________________________
Cl: __________________________
C4H10
C: __________________________
H: __________________________
K2CO3
K: __________________________
C: __________________________
O: __________________________
Ag2SO4
Ag: __________________________
S:
__________________________
O: __________________________
C12H22O11
C: __________________________
H: __________________________
O: __________________________
HBr
H: __________________________
Br: __________________________
Solve the following problems using stoichiometric calculations.
Convert 3.5 grams of NaCl to molecules of NaCl.
How many atoms of hydrogen are in 4.28 grams of (NH4)2SO4?
How many grams of CaCO3 are in 0.784 moles of CaCO3?
How many grams of phosphorus are in 22.3 grams of P2O5?
How many grams of water can be made with 3.17 grams of hydrogen gas in excess oxygen gas?
2H2 + O2  2H2O
Solve the following problems for the specified empirical and/or molecular formula.
Find the empirical formula for a compound which contains 32.8% chromium and 67.2%
chlorine.
What is the empirical formula for a compound which contains 67.1% zinc and the rest is
oxygen?
The empirical formula of a substance is CH2O. The molar mass is 180g/mol, what is the
molecular formula?
A compound containing 5.9265% H and 94.0735% O has a molar mass of 34.01468 g/mol.
Determine the empirical and molecular formula of this compound.
What is the empirical formula for a compound which contains 0.0134g of iron, 0.00769g of
sulfur, and 0.0115g of oxygen? What is the molecular formula if the molar mass is 407.55g/mol?
Solve the following limiting reactant problems.
If 13.2 grams of nitrogen and 17.0 grams of hydrogen are used, how many grams of ammonia
can be made?
N2 + 3H2  2NH3
How much carbon dioxide in grams can be produced by combusting 14.5 grams of octane
(C8H18) in a controlled 25 gram amount of oxygen gas?
2C8H18 + 25O2  16CO2 + 18H2O
How much of the excess reactant in grams is left over when reacting 4.96 grams of nitric acid
with 7.28 grams of barium hydroxide?
2HNO3 + Ba(OH)2  Ba(NO3)2 + 2H2O
How many moles of salt can be produced by reacting 42 moles each of solid sodium and chlorine
gas?
2Na + Cl2  2NaCl
Calculate the percent yield for each of the following problems. *Be aware that you may
need to find the limiting reactant first if not otherwise specified.
If 25 grams of iron (III) phosphate reacts with excess sodium sulfate, how many grams of iron
(III) sulfate can be produced? If 18.5 grams are actually produced, what is the percent yield?
2FePO4 + 3Na2SO4  Fe2(SO4)3 + 2Na3PO4
If 30 grams of ammonium nitrate reacts with 50 grams of sodium phosphate, how many grams of
sodium nitrate will form? If 28.3 grams is synthesized in lab, what is the percent yield?
3NH4NO3 + Na3PO4  (NH4)3PO4 + 3NaNO3
If 100 grams of calcium carbonate reacts with 45 grams of iron (II) phosphate, how many grams
of calcium phosphate can be made? If we obtain 78% yield, how much was the actual yield?
3CaCO3 + Fe3(PO4)2  Ca3(PO4)2 + 3FeCO3