Stoichiometry
Practice Test
1.
How is the slope of a linear graph calculated?
a.
slope = (y
2
– y
1
) / (x
2
– x
1
)
b.
slope = (x
2
– x
1
) / (y
2
– y
1
)
c.
slope = (x
2
– x
1
) / 100
d.
slope = (y
2
– y
1
) x 100
2.
How many particles are present in one mole of particles?
a.
1
b.
6.02 x 10
23
c.
12
d.
3.0 x 10
8
3.
The substance that limits the extent of a chemical reaction has a special name. What is this substance called?
a.
excess product
b.
excess reactant
c.
limiting reactant
d.
limiting product
4.
Balance the following equation with the smallest whole—number coefficients. How many grams of O
2
will be produced if 23.2 g of XeF
2
reacts with excess water?
XeF
2
+ H
2
O → Xe + HF + O
2
a.
1.10 g
b.
3.31 g
c.
2.19 g
d.
4.42 g
5.
What do the coefficients in the following balanced chemical equation mean?
2H
2
+ O
2
→ 2H
2
O
a.
2 moles of hydrogen and 1 mole of oxygen in the products
b.
2 moles of hydrogen and 1 mole of oxygen in the reactants
c.
2 moles of oxygen and 1 mole of hydrogen in the reactants
d.
2 moles of oxygen and 1 mole of hydrogen in the products
6.
Determine the number of atoms in 3.54 mol S.
a.
2.13 x 10
24
b.
1.70 x 10
24
c.
1.70 x 10
23
d.
2.13 x 10
23
7.
What is the mass of one mole of carbon-12 atoms?
a.
6 amu
b.
12 amu
c.
12 grams
d.
6 grams
8.
What is the percent yield of CO
2
if a reaction using 10.0 g CO with excess O
2
produces 12.8 g CO
2
?
2CO + O
2
→ 2CO
2
a.
76.40%
b.
81.50%
c.
84.40%
d.
78.10%
9.
Analysis of a covalent compound showed that it contained 14.4% hydrogen and 85.6% carbon by mass. What is the empirical formula for this compound?
a.
CH
3
b.
CH
c.
C
2
H
3
d.
CH
2
10.
Dimensional analysis is a method of problem-solving that focuses on ________ .
a.
accuracy
b.
error
c.
units
d.
precision
11.
The representation of data on graph that resembles a pizza is a _________.
a.
circle graph
b.
inverse
c.
bar graph
d.
line graph
12.
What mass of iron is contained in 62.8 grams of pyrite FeS
2
?
a.
29.2 g
b.
40.3 g
c.
31.7 g
d.
58.5 g
13.
Calculate the number of moles of hydrogen atoms in 4.75 mol sulfuric acid.
a.
4.75 mol
b.
33.2 mol
c.
2.38 mol
d.
9.50 mol
14.
How many moles of CO
2
would be produced from 56 moles of O
2
according to the following balanced equation?
2C
2
H
6
+ 7O
2
→ 4CO
2
+ 6H
2
O
a.
224 mol
b.
48 mol
c.
32 mol
d.
16 mol
15.
Based on the following equation, how many moles of hydrochloric acid are needed to react with 0.64 moles of potassium permanganate?
2KMnO
4
+ 8 HCl → 3 Cl
2
+ 2 MnO
2
+ 4 H
2
O + 2KCl
a.
0.21 mol HCl
b.
5.1 mol HCl
c.
2.7 mol HCl
d.
0.64 mol HCl
16.
How many milliliters are there in 1.0 microliter?
a.
1.0 x 10
-3
mL
b.
1.0 x 10
-1
mL
c.
1.0 x 10
-4
mL
d.
1.0 x 10
-2
mL
17.
How is one gram defined?
a.
10 moles of amu
b.
one mole of protons
c.
one mole of amu
d.
0.1 mole of amu
18.
How many moles of HCl will just react with 0.424 g Ba(OH)
2
?
2HCl + Ba(OH)
2
→ BaCl
2
+ 2H
2
O
a.
2.48 x 10
-3
mol
b.
1.24 x10
-3
mol
c.
4.94 x 10
-3
mol
d.
9.90 x 10
-3
mol
19.
The reaction of 5.0 grams of fluorine with excess chlorine produced 5.6 grams of ClF
3
. What percent yield of ClF
3
was obtained?
Cl
2
+ 3F
2
→ 2ClF
3
a.
69%
b.
86%
c.
76%
d.
58%
