Phosphoric acid is a common ingredient in many food products. Food-grade phosphoric acid is used to acidify foods and beverages. It provides a tangy or sour taste to many sodas and colas. Identify the chemical formula for phosphoric acid.
A. HCl B. H
2
SO
4
C. HNO
3
D. H
3
PO
4
Polyprotic acids are capable of donating more than a single proton per molecule in acid-base reactions. Protons are lost through several stages, with the first proton being the fastest and most easily lost. Identify the polyprotic acid below.
A. HCl B. H
2
SO
4
C. HBr D. HNO
3
As determined by the percent disassociation, which of the following acids can be classified as a strong acid?
B. 90% disassociation A. 100% disassociation
C. 80% disassociation D. All of the above
If the pOH of an unknown solution is 7.5 what is the solution’s pH?
A. 5.5 B. 6.5 C. 7.5 D. 8.0

A solution has a hydrogen ion concentration [H
+
] of 1 × 10 -3 molar. What is the pH of the solution?
A. 0.001 B. 0.01 C. 0.3 D. 3.0
A NH
3 solution in water has a hydronium ion (H
3
O + ) concentration of
2.50 × 10
-11 molar. What is the pH of the NH
3 solution?
A. 2.00 B. 3.40 C. 10.6 D. 11.0
An unknown compound has the empirical formula C
2
HO
2
. Which of the following molecular formulas corresponds to the given empirical formula?
A. C
7
H
2
O
7
B. C
6
H
3
O
6
C. C
5
HO
2
D. C
4
H
2
O
2
A sample of a compound was found to contain 54 grams (2 moles) of aluminum, 96 grams (6 moles) of oxygen, and 6 grams (6 moles) of hydrogen. What is the empirical formula of this compound?
A. Al
6
OH B. AlO
3
H
3
C. Al
3
O
3
H
3
D. Al
2
O
6
H
6

Use the reaction equation to answer the question.
CH
4
( g ) + 2O
2
( g ) CO
2
( g ) + 2H
2
O( g )
The equation represents methane gas (CH
4
) burning in oxygen gas (O
2
). If
32 grams (2 moles) of methane are burned, how many grams of carbon dioxide (CO
2
) are produced?
A. 28 grams B. 44 grams C. 56 grams D. 88 grams
Use the reaction equation to answer the question.
PCl
3
+ 3H
2
O H
3
PO
3
+ _ ?
_HCl
The equation shows a reaction between phosphorus tri-chloride (PCl
3
) and water (H
2
O). How many moles of hydrogen chloride (HCl) are needed to balance the equation?
A. 1 mole B. 2 moles C. 3 moles D. 6 moles
Use a periodic table to determine how many grams are in two moles of glucose (C
6
H
12
O
6
).
A. 90 grams B. 180 grams C. 360 grams D. 400 grams

The diagram shows the structural formula for cis-2-butene. Which property allows this molecule to be classified as an alkene?
A. It has an even number of carbon atoms.
B. It has a double bond between carbon atoms.
C. It includes methyl groups attached to carbon atoms.
D. It is a symmetrical molecule.
Which structural formula represents n-pentane (straight chain pentane)?
A.
B.
C.
D.

Which of the following chemical reactions is correctly balanced?
A. 3HCl + NaOH  3H
2
O + NaCl
B. 2HCl + 2NaOH  H
2
O + NaCl
C. HCl + NaOH  2H
2
O + NaCl
D. HCl + NaOH  H
2
O + NaCl
Which of the following chemical reactions is correctly balanced?
A. 6CO
2
+ 6H
2
O  C
6
H
12
O
6
+ 6O
2
B. 3CO
2
+ 3H
2
O  C
6
H
12
O
6
+ 3O
2
C. 2CO
2
+ 2H
2
O  C
6
H
12
O
6
+ 2O
2
D. CO
2
+ H
2
O  C
6
H
12
O
6
+ O
2
According to the law of conservation of matter, what happens to the atoms in a chemical reaction?
A. The atoms are rearranged with no loss in mass.
B. Some atoms are destroyed, resulting in mass being converted to energy.
C. There is a small gain in mass as new atomic bonds are formed.
D. The atoms remain unchanged with no change in mass.

Use the model to answer the question.
What is the name of the compound represented by this model?
A. n-hexane
B. 3-methyl-butane
C. 2-ethyl-pentane
D. 3-methyl-pentane
Using Lavoisier’s Law of Conservation of Mass, determine how many grams of O
2
would be created if 80.6 grams of MgO is decomposed as in the following reaction:
2MgO  2Mg + O
2
80.6 grams 48.6 grams
A. 10.0 grams B. 26.0 grams C. 28.0 grams D. 32.0 grams

Herbert prepared the table in order to classify different hydrocarbons according to their structure.
A.
C.
Which list correctly classifies these hydrocarbons?
A. 1 – alkyne; 2 – alkane; 3 – alkene; 4 – alkane
B. 1 – alkene; 2 – alkane; 3 – alkyne; 4 – alkane
C. 1 – alkane; 2 – alkene; 3 – alkyne; 4 – alkene
D. 1 – alkene; 2 – alkyne; 3 – alkane; 4 – alkyne
Which of the following molecules is an alcohol?
B.
D.

Based on the given solubility rules, which of the equations below shows a precipitate that is actually soluble in water?
A. 2NaCl( aq ) + Ca(OH)
2
( aq )  2NaOH( s ) + CaCl
2
( aq )
B. BaCl
2
( aq ) + Na
2
SO
4
( aq )  BaSO
4
( s ) + 2NaCl( aq )
C. MgSO
4
+ Na
2
CO
3
 MgCO
3
( s ) + Na
2
SO
4
( aq )
D. 3KCl( aq ) + (NH
4
)
3
PO
4
( aq )  K
3
PO
4
( s ) + 3NH
4
Cl( aq )
Identify the type of chemical reaction represented by the following reaction formula:
HBr + NaOH  NaBr + H
2
O
A. a decomposition
C. a double-displacement reaction
B. an acid-base reaction
D. a combustion reaction
Identify the type of chemical reaction represented by the following reaction formula:
2H
2
O  2H
2
+ O
2
A. a decomposition
C. a double-displacement reaction
B. an acid-base reaction
D. a combustion reaction

Identify the type of chemical reaction represented by the following reaction formula:
C
10
H
8
+ 12O
2
 10CO
2
+ 4H
2
O
A. a decomposition
C. a double-displacement reaction
B. an acid-base reaction
D. a combustion reaction
Identify the type of chemical reaction represented by the following reaction formula:
Pb(NO
3
)
2
+ 2KI  PbI
2
+ 2KNO
3
A. a decomposition
C. a double-displacement reaction
B. an acid-base reaction
D. a combustion reaction
Avogadro's number is the number of particles found in one mole of a substance and its value is:
A. 6.022 x 10 23
C. 6.020 x 10 23
B. 6.023 x 10 22
D. 6.020 x 10 22

What is the percent yield for a chemical reaction in which the theoretical yield of hydrogen cyanide (HCN) is 190 grams, but the actual yield is 156 grams?
A. 90.1% B. 82.1% C. 80.0% D. 74.5%