WorksheetsChemistry Unit 5 Test Review: Stoichiometry
Total questions: 20
Worksheet time: 10mins
Name
Class
Date
1.
What is the molar mass of sodium bromide, NaBr?
a)
45.0 g/mol
b)
58.5 g/mol
c)
102.9 g/mol
d)
150.2 g/mol
2.
3.5×10^22 atoms of oxygen would weigh how many grams?
a)
0.93 g
b)
1.55 g
c)
3.73 g
d)
5.18 g
3.
What is the molar mass of SO₂?
a)
32.1 g/mol
b)
48.1 g/mol
c)
64.1 g/mol
d)
80.1 g/mol
4.
How many moles are there in 9.03×10^23 molecules of methane (CH₄)?
a)
0.15 mol
b)
3.0 mol
c)
4.5 mol
d)
1.5 mol
5.
A compound has empirical formula CH₂ and molar mass 56 g/mol. What is its molecular formula?
a)
CH₂
b)
C₂H₄
c)
C₃H₆
d)
C₄H₈
6.
Convert 150.0 g of CuCl₂ to moles.
a)
0.56 mol
b)
1.12 mol
c)
2.25 mol
d)
5.50 mol
7.
One mole of iron weighs 55.85 g. How many atoms are in 111.7 g?
a)
6.02×10²³
b)
1.20×10²⁴
c)
3.01×10²⁴
d)
6.70×10²⁴
8.
What is the mass in grams of 3.50 moles of KI?
a)
0.29 g
b)
58.3 g
c)
290 g
d)
581 g
9.
4 Fe + 3 O₂ → 2 Fe₂O₃
How many moles of Fe₂O₃ will form from 12.0 moles of O₂?
a)
4.0 mol
b)
6.0 mol
c)
8.0 mol
d)
12.0 mol
10.
2 KClO₃ → 2 KCl + 3 O₂
How many grams of O₂ are produced from 25.0 g of KClO₃?
a)
4.92 g
b)
9.8 g
c)
12.3 g
d)
18.9 g
11.
2 Na + Cl₂ → 2 NaCl
How many atoms of NaCl are produced from 10.0 g of Na?
a)
4.37×10²³
b)
2.62×10²³
c)
1.31×10²⁴
d)
2.62×10²⁴
12.
Which is true of a limiting reagent?
I. It is a reactant
II. It limits product
III. It determines maximum product
a)
I only
b)
II only
c)
I and II only
d)
I, II, and III
13.
A student expected 10.0 g of product but obtained 8.5 g. What was the percent yield?
a)
15%
b)
75%
c)
85%
d)
118%
14.
NaOH + HCl → NaCl + H₂O
After reaction, NaCl, water, and NaOH were present. Which was limiting?
a)
NaOH
b)
HCl
c)
NaCl
d)
H₂O
15.
What is the molarity of a solution made by dissolving 2.0 moles of sodium chloride (NaCl) in 1.0 L of water?
a)
0.50 M
b)
1.0 M
c)
2.0 M
d)
4.0 M
16.
A student dissolves 5.0 grams of glucose (C₆H₁₂O₆) in enough water to make 0.50 L of solution. What is the molarity of the solution? (Molar mass of glucose = 180 g/mol.)
a)
0.028 M
b)
0.056 M
c)
0.18 M
d)
2.80 M
17.
A solution contains 0.25 moles of hydrochloric acid (HCl) dissolved in 2.5 L of water. What is its molarity?
a)
0.10 M
b)
0.25 M
c)
0.50 M
d)
1.0 M
18.
In a reaction, the theoretical yield of magnesium oxide is 5.0 g. When the reaction was performed in the lab, the actual yield was 4.2 g.
What is the percent yield of this reaction?
a)
84%
b)
120%
c)
95%
d)
15%
19.
A student was supposed to produce 10.0 g of copper, but only actually obtained 7.5 g during a single-replacement reaction.
What is the percentage yield?
a)
25%
b)
75%
c)
95%
d)
133%
20.
Balance the following double-replacement reaction using the lowest whole-number coefficients:
AgNO₃ + Na₂S → Ag₂S + NaNO₃
a)
2AgNO₃ + Na₂S → Ag₂S + 2NaNO₃
b)
AgNO₃ + Na₂S → 2Ag₂S + NaNO₃
c)
2AgNO₃ + 2Na₂S → Ag₂S + NaNO₃
d)
AgNO₃ + Na₂S → Ag₂S + NaNO₃
100 %
