Houston Community College System
Chemistry 1305
EXAM # 2
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HOUSTON COMMUNITY COLLEGE
CHEM 1305
Name: _____________________
Exam # 2 (Chap. 5- 7)
Score:
PART I – Multiple choice: (3 points each)
1) The elements lithium, sodium, and potassium
a) are isotopes of each other.
c) have the same number of neutrons.
e) have the same mass number.
b) are in the same period of elements.
d) are in the same group.
2) The correct symbol for the isotope of potassium with 22 neutrons is
a)
41
19
K
b)
19
41
K
c)
37
15
P
d)
15
37
P
e)
22
19
K
3) Which of the following gives the correct numbers of protons, neutrons, and electrons
in a neutral atom of 118
50 Sn ?
a) 118 protons, 50 neutrons, 118 electrons
b) 118 protons, 118 neutrons, 50 electrons
c) 50 protons, 68 neutrons, 50 electrons
d) 68 protons, 68 neutrons, 50 electrons
e) 50 protons, 50 neutrons, 50 electrons
4) What is the frequency of radiation that has a wavelength of 0.589 pm?
a) 1.96 x 10-21 Hz
c) 5.09 x 108 Hz
b) 5.09 Hz
d) 5.09 x 1020 Hz
5) The maximum number of electrons that may occupy the fourth electron energy level is
a) 2.
b) 8.
c) 10.
d) 18.
e) 32.
6) How many of the following pairs of elements and symbols are entirely correct?
Phosphorus(P) ; Aluminum(Au) ; iron(Fe); krypton (K)
a) 0
b) 1
c) 2
d) 3
7) Ionization energy is
a) the energy an ion acquires from an electron.
b) the energy needed to remove the least tightly bound electron.
c) highest for metals in Group 1A(1).
d) higher for potassium than for lithium.
e) none of the above
2
e) 4
e) 1.96 x 10-22 Hz
8) Which of these isotopes has the greatest of number of neutrons?
a) 38Cl
b) 40Ar
c) 40K
d) 40Ca
e) 38Sc
9) Which of the following is an alkaline earth metal?
a) Al
b) Fe
c) Si
d) Ca
e) Cl
10) What charge is present on a oxalate ion?
a) -1
b) +1
c) -2
d) +2
e) 0
11) The compound CaCO3 is classified as which of the following?
a) binary ionic
b) ternary molecular
c) ternary ionic
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d) binary acid
e) none
12) What is the name for Fe+3?
a) iron ion
b) iron (II) ion
c) ferrous ion
d) ferric (III) ion
e) ferric ion
13) What is the name for Se2-?
a) selenium ion
b) selenium (II) ion
c) selenite ion
d) selenide ion
e) this ion does not exist
14) Each response below lists an ion by name and by chemical symbol or formula. Also each ion is classified as
monatomic or polyatomic and as a cation or anion. Which choice contains an error?
a) bicarbonate, HCO3 -, polyatomic anion
c) magnesium, Mg2+, monatomic cation
e) sulfite, SO3 2-, polyatomic anion
b) ammonium, NH4 +, polyatomic cation
d) hydroxide, OH-, monatomic anion
15) What is the predicted ionic charge of an element in Group VIA?
a) 2+
b) 6+
c) 2-
d) 6-
e) 8
16) What is the systematic name for Cr2O72-?
a) chromide ion
b) chromite ion
c) chromate ion
d) chromium ion
e) dichromate ion
17) What is the formula for the ionic compound formed by calcium ions and phosphate ions?
a) CaPO4
b) Ca 2(PO4)2
c) Ca (PO4)3
d) Ca 3PO4
e) Ca 3(PO4)2
18) When it is correctly balanced, the correct coefficients for the equation below are:
PH3 + O2 
a) 2, 2, 1, 3
b) 4, 6, 1, 6
c) 4, 3, 2, 3
P4O6 + H2O
d) 2, 3, 2, 3
e) 3,3,1,1
19) In a molecule with covalent bonding,
a) oppositely charged ions are held together by strong electrical attractions.
b) atoms of metals form bonds to atoms of nonmetals.
c) atoms of different metals form bonds.
d) atoms are held together by sharing electrons.
e) atoms of noble gases are held together by attractions between oppositely charged ions.
20) What is the classification for this unbalanced reaction?
Fe+HCl  FeCl3  H2
a) dehydration
d) single replacement
b) combination
e) double replacement
c) decomposition
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PART II – Show All Your Work: (8 points each)
21) Match the correct name of the polyatomic ions with the formulas given.
1) NO 3 
A) phosphate
2) CO 3 2 
B) hydroxide
3) SO 4 2
C) oxide
4) SO32
D) hydrogen carbonate
5) PO 43
E) sulfite
6) NO 2 
F) phosphite
7) HCO3
G) nitrite
8) HSO 4 
H) nitrate
9) OH 
I) hydrogen sulfate
J) sulfate
K) carbonite
L) carbonate
M) hydrogen sulfite
22) Which of the following metals does not react with aqueous Cr2(SO4)3? Why? Show the chemical equations
for those reactions that take place.
Partial Activity Series: Ca > Zn > Cr> (H) > Ag > Au
23) Indicate the type of bonding you would expect between the following elements.
1) Na and F
2) N and F
3) F and F
4) He and F
5) H and F
A) none
B) nonpolar covalent
C) polar covalent
D) ionic
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24) Match the chemical name with the correct formula.
1) magnesium sulfate
A) Mg(HSO3 )2
2) magnesium hydrogen sulfate
3) magnesium sulfide
4) magnesium sulfite
B) MgSO3
C) MgS
D) Mg(HSO4 )2
5) magnesium hydrogen sulfite
E) MgSO4
25) What is the core notation for the electron configuration of a germanium atom?
BONUS QUESTION – Show All Your Work: (1 point each- 10 points)
1. Name each chemical formula
A. I2O5
B. Fe(NO3)2
C. PbO
D. Na2O2
E. Sn(SO4)2
2. What is the chemical formula for each name given?
A. ferric oxide
B. calcium hydroxide
C. tetrasulfur dinitride
D. potassium chlorite
E. gallium (III) phosphide
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ANSWERS:
1. D 2. A
15. C
16. E
3. C
4. D
17. E
5. E
18. B
6. C
19. D
7. B
8. B
9. D
10. C
11. C
20. D
21. 1-H; 2-L; 3-J; 4-E; 5-A; 6-G; 7-D; 8-I; 9-B
22. 3 Ca + Cr2(SO4)3  3CaSO4 + 2Cr
3 Zn + Cr2(SO4)3  3ZnSO4 + 2Cr
23. 1-D; 2-C; 3-B; 4-A; 5-C
24. 1-E; 2-D; 3-C; 4-B; 5-A
25. Ge 32 e-
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p2
Bonus
1. A. diiodine pentoxide; B. iron (II) nitrate or ferrous nitrate; C. lead (II) oxide;
D. sodium peroxide; E. tin (IV) sulfate
2. A. Fe2O3; B. Ca(OH)2; C. S4N2; D. KClO2; E. GaP
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12. E
13. D
14. D