Houston Community College System
Chemistry 1405
EXAM # 2
Activity Series:
Li > K > Ba > Sr > Ca > Na > Mg > Al > Mn > Zn > Fe > Cd > Co > Ni > Sn > Pb > (H) > Cu > Ag > Hg > Au
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HOUSTON COMMUNITY COLLEGE
CHEM 1405
Name: _____________________
Exam # 2 (Chap. 5- 8)
Score:
PART I – Multiple choice: (3 points each)
1) Which of the following is a p-block element?
A) Al
B) Si
C) F
D) all of the above
2) Identify the correct statement about the atomic radius or size.
a) Na atom is smaller than Mg atom
c) Ge atom is smaller than C atom
b) P atom is smaller than Si atom
d) Ba atom is smaller than Sr atom
3) Identify the element which has more metallic character
A) Sc
B) K
C) Fe
D) Ge
4) The compound Al2(SO4)3 is classified as which of the following compound?
A) Binary ionic
B) Ternary ionic
C) Binary molecular
D) Binary acid
5) What is the name for Cr2O3?
A) Chromium(I) oxide
B) Chromium(II) oxide C) Chromium(III) oxide
D) Chromium(IV) oxide
6) What is the systematic name of N3 ?
A) Nitrite ion
B) Nitrate ion
C) Nitride ion
D) Nitrogen ion
7) What is the chemical formula for the Iron(II) iodide?
A) FeI
B) FeI2
C) IrI2
D) FeI4
8) What is the name of a reaction in which two cations (positive ions) in different compounds exchange anions
(negative ions)?
A) Combination
B) decomposition
C) double replacement
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D) neutralization
9) Which of the statements below best describes the following reaction?
K2CO3(s)  K2O(s) + CO2(g)
A) It is a combination reaction
B) It is a neutralization reaction.
C) It is a decomposition reaction.
D) It is a special class of reaction.
10) What is the coefficient of oxygen gas after balancing the following equation?
___C6H6 + ___O2 → ___CO2 + ___H2O
A) 6
B) 15
C) 11
D) 12
11) What is the Coefficient of Ba(NO3)2 after balancing the following equation?
__ Al2(SO4)3 + ___Ba(NO3)2
A) 3
C) None.
→
BaSO4 + ___Al(NO3)3
B) 2
D) 4
12) Which of the following electron configurations for the species in their ground state are correct?
i.
ii.
iii.
iv.
v.
A. All of them
K: 1s22s22p63s23p64s1
Mn: [Ar]4s24d5
Sc: [Ar] 4s24p1
Fe: [Ar] 4s23d6
Al: [Ne] 3s22d103p1
B. None of them
C. i & iv
D. v & iii
E. i,iii & v
13) Classify the following reaction
H2SO4 + Mg(OH)2 → MgSO4 + H2O
A) Combination
B) Double replacement
C) Single replacement
D) Neutralization
14) Classify the following reaction
2Na + 2H2O → 2NaOH + H2
A) Combination
B) Single Replacement
C) Decomposition
15) Identify the correct statement about 1 mole carbon
A) Equals 12.01 g
C) Equals 6.02 x 1023 Carbon atoms
B) Equals 2 moles of Hydrogen
D) A and B
E) A and C
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D) None of them
16) How many Boron atoms make 23g of Boron:
A) 3.1 x 1023 atoms
D) 4.3 x 1021 atoms
B) 1.28 x 1024 atoms
E) None of them
C) 5.1 x 1020 atoms
17) Empirical formula of an organic compound is C2H3O. If the molar mass is 129.15g/mole, what is the
molecular formula?
A) CHO
B) C8H16O4
C) C6H9O3
D) C4H6O2
E) None of them
18) What is the percent of Hydrogen in C2H5OH?
A) 31%
B) 13%
C) 18%
D) 21%
E) 24%
19) Calculate mass of carbon in 2.4 moles of carbon dioxide.
A) 2.4 g
B) 8.4g
C) 14.4g
D) 20.3g
20) Calculate the number of Hydrogen atoms in 2.2 moles of Ethane (C2H6) gas?
A) 7.94 x 1024 B) 6.02 x 1023
C) 3.01 x 1024
D) 1.32 x 1024
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PART II – Show All Your Work: (8 points each)
1) Balance the following reactions and classify them
→ _____AlPO3 + _____ O2
A)
____AlPO4 (s)
B)
___Zn (s) + ___Pb(NO3)2 (aq) →
___ZnNO3 (aq) + Pb (s)
2) Write formula of the products in the following reactions
A) Al + O2
→
B) Al + Cl2
→
3) Balance and Determine whether the following reaction proceeds or not? (See the activity series)
A) CaCl2 + Fe →
B) Al
Ca + FeCl2
+ SnSO4 → Al2(SO4)3 +Sn
4) What is the name of each compound?
a. Al2S3
b. KCl
c. Cr2O3
d. MnO2
5) Fill in the blanks
Empirical formula
CH2
Molar mass (g/mol)
42.08
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Molecular formula
C3H6O2
CHN
74.09
135.15
C2H2O4
C8H16Cl2
Bonus Question (5 points):
Chlorine is prepared industrially by heating hydrogen chloride gas with oxygen gas. Assuming that the only
products formed in the process are chlorine gas and water, write the chemical equation and balance the equation
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