2014 Spring CHEM101 Ch3 Review Worksheet Modified by Dr

2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,
1): Match each diagram with its correct description. Diagrams will be used once.
A
B
C
D
E
_C_1. Pure Element – only one type of atom present.
_E_2. Mixture of two elements – two types of uncombined atoms present.
_B_3. Pure compound – only one type of compound present.
_A_4. Mixture of two compounds – two types of compounds present.
_D_5. Mixture of a compound and an element.
2) Which diagram represents a pure compound ?
A
B
C
D
E
3) Which of the following drawings represents a collection of acetylene (C2H2) molecules? The shaded spheres
represent carbon atoms and the unshaded spheres represent hydrogen atoms.
A) drawing (a)
B) drawing (b)
C) drawing (c)
D) drawing (d)
Answer: C
4) If unshaded spheres represent sulfur atoms and shaded spheres represent oxygen atoms, which of the following
2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,
drawings depicts a collection of sulfur trioxide molecules?
A) drawing (a)
B) drawing (b)
C) drawing (c)
D) drawing (d)
Answer: D
5) Which of the following is an ionic compound?
A) SF2
B) Mg3(PO4)2
C) Cl2O
D) CH2O
E) PBr5
Answer: B
6) Which of the following is a molecular compound?
A) KCN
B) LiOH
C) SrI2
D) ZnS
E) P4O10
Answer: E
7) The fundamental SI unit for measuring matter is the ________.
Answer: mole
8) To the nearest whole number, the molar mass of AlCl3 is ________ g/mol.
9) To the nearest whole number, the molar mass of Cu(NO3)2 is ________ g/mol.
Answer: 188
10) The number of grams in 0.333 mol of urea, (NH2)2CO, is ________.
Answer: 20.0 g
Topic: Section 3.3 Chemical Arithmetic: Stoichiometry
11) How many moles are in 7.8 g of acetamide, CH3CONH2?
Answer: 0.13
Topic: Section 3.3 Chemical Arithmetic: Stoichiometry
12) Please calculate the 2 following formula mass of NH3 and NO3. What is each element composition in each
2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,
compound?
13) Calculate the molar mass of H2CO3.
A) 62.03 g/mol
B) 29.02 g/mol
C) 61.02 g/mol
D) 60.01 g/mol
E) 74.04 g/mol
Answer: A
14) Determine the molecular formula of a compound that has a molar mass of 92.0 g/mol and an empirical formula
of NO2.
A) N2O3
B) N3O6
C) N2O4
D) NO2
E) N2O5
Answer: C
15) Combustion analysis of 63.8 mg of a C, H and O containing compound produced 145.0 mg of CO2 and 59.38
mg of H2O. What is the empirical formula for the compound?
A) C5H2O
B) CHO
C) C3H6O
D) C3H7O
E) C6HO3
Answer: C
16) What is the empirical formula of a substance that contains 2.64 g of C, 0.444 g of H, and
3.52 g of O?
A) CH2O
B) C2H4O2
C) C2H4O3
D) C3H4O4
Answer: A
17) What is the empirical formula of a substance that contains 27.27% carbon and 72.73% oxygen ?
18) Which one of the following is not an empirical formula?
A) CHO
B) CH2O
C) C2H4O
D) C2H4O2
Answer: D
19) How many C2H4 molecules are contained in 45.8 mg of C2H4? The molar mass of C2H4 is 28.05 g/mol.
2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,
A) 9.83 × 1020 C2H4 molecules
B) 7.74 × 1026 C2H4 molecules
C) 2.71 × 1020 C2H4 molecules
D) 3.69 × 1023 C2H4 molecules
E) 4.69 × 1023 C2H4 molecules
Answer: A
20) How many carbon atom are founded in 10 g of C2H4? The molar mass of C2H4 is 28.05 g/mol.
21) When the reaction C4H10 + O2 → CO2 + H2O is balanced using the smallest whole number coefficients, the
coefficient in front of O2 is ________.
Answer: 13
22) When the reaction C3H8 + O2 → CO2 + H2O is balanced, the total number of oxygen atoms in the balanced
equation is ________.
Answer: 40
23) Write a balanced equation to show the reaction of gaseous ethane with gaseous oxygen to form carbon
monoxide gas and water vapor.
A) 2 C2H6(g) + 7 O2(g) → 4 CO2(g) + 6 H2O(g)
B) C2H6(g) + 5 O(g) → 2 CO(g) + 3 H2O(g)
C) 2 C2H6(g) + 5 O2(g) → 4 CO(g) + 6 H2O(g)
D) C2H6(g) + 7 O(g) → 2 CO2(g) + 3 H2O(g)
E) 2 CH3(g) + 5 O(g) → 2 CO(g) + 3 H2O(g)
Answer: C
24) If unshaded spheres represent nitrogen atoms and shaded spheres represent oxygen atoms, which box represents
reactants and which represents products for the reaction 2 NO2(g) → 2 NO(g) + O2 (g)?
A) box (a) reactants and box (b) products
B) box (a) reactants and box (d) products
C) box (c) reactants and box (b) products
D) box (c) reactants and box (d) products
Answer: D
25) If unshaded spheres represent nitrogen atoms and shaded spheres represent oxygen atoms, which box represents
reactants and which represents products for the reaction 2 N2O (g) → 2 N2(g) + O2(g)?
2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,
A) box (a) reactants and box (c) products
B) box (a) reactants and box (d) products
C) box (b) reactants and box (c) products
D) box (b) reactants and box (d) products
Answer: B
26) Reaction of A (unshaded spheres) with B2 (shaded spheres) is shown schematically in the following diagram.
Which equation best describes the stoichiometry of the reaction?
A) A2 + 2 B → A2B2
B) 8 A + 4 B2 → 4 A2B2
C) 2 A + B2 → A2B2
D) 4 A + 4 B2 → 4 A2B2
Answer: C
27) To the nearest whole number, the molar mass of AlCl3 is ________ g/mol .
Give the name of this compound.
28) Give the name for KMnO4.
A) potassium manganese tetraoxide
B) potassium manganate
C) potassium permanganate
D) potassium permagnesium
E) potassium magnesate
Answer: C
29) What is the name of SO2 and SO3 ?
SO2 is sulfur dioxide,
SO3 is sulfur trioxide,.
30) Give the correct formula for aluminum sulfate.
A) Al2SO4
B) Al(SO4)3
2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,
C) Al3(SO4)2
D) Al2(SO4)3
Answer: D
31) Write the formula for copper (II) sulfate pentahydrate.
A) Cu2SO3∙H5
B) Cu2S∙H2O
C) CuS∙5H2O
D) (CuSO4)5
E) CuSO4∙5H2O
Answer: E
32) Give the name for SnO.
A) tin (I) oxide
B) tin (II) oxide
C) tin (III) oxide
D) tin (IV) oxide
Answer: B
33) What is the name of Zn3(PO4)2, and Cu 3 (PO4) 2?
34) The formula of Potassium permanganate is KMnO4. What is the formula of aluminum permanganate ?
35) Determine the name for H2CO3.
A) carbonous acid
B) dihydrogen carbonate
C) carbonic acid
D) hydrocarbonic acid
E) hydrocarbide acid
Answer: C
2014 Spring CHEM101 Ch3 Review Worksheet
Modified by Dr. Cheng-Yu Lai,