Download test2 contoh(30sept 2010) Word document - e

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SECTION A
Mark your answers in the answer sheet provided.
(NA = 6.022 x 1023)
1. Electrons in an orbital with l = 3 are in a/an
A) d orbital.
B) f orbital.
C) g orbital.
D) p orbital.
E) s orbital.
2. What is the charge on the monatomic ion of nitrogen, the nitride ion?
A) +2
C) –1
B) +1
D) –2
E) –3
3. No two electrons in an atom can have the same four quantum numbers" is a statement of
A)
the Pauli exclusion principle.
D)
de Broglie's relation.
B)
Bohr's equation.
E)
Dalton's atomic theory.
C)
Hund's rule.
4. What is the maximum number of electrons in an atom that can have the following set of quantum numbers?
n=4
l= 3
ml = –2
A) 0
ms = +1/2
B) 1
C) 2
D) 6
E) 10
5. The elements in Group 17 are known by what name?
A)
transition metals
D)
alkaline earth metals
B)
halogens
E)
noble gases
C)
alkali metals
6. The alkali metal elements are found in _______ of the periodic table.
A) Group 1
B) Group 2
C) Group 13
D) Period 7
E) Period 1
7. The general electron configuration for atoms of all elements in Group 15 is
A) ns2np6
B) ns2np5
C) ns2np4
D) ns2np3
E) ns2np1
8. In what row and group of the periodic table would you find the element with the electron configuration
[Kr]5s24d105p2?
A)
row 4, group 14
D)
row 5, group 15
B)
row 4, group 15
E)
row 5, group 16
C)
row 5, group 14
9. Which one of the following is most likely to be an ionic compound?
A) NCl3
B) BaCl2
C) CO
D) SO2
E) SF4
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10. Which ground-state atom has an electron configuration described by the following orbital diagram?
A) phosphorus B) germanium C) selenium
D) tellurium
E) sulfur
11. Which choice lists two elements with ground-state electron configurations that are well known exception
to the Aufbau principle?
A) Cu and C
B) Cr and Cu
C) Cs and Cl
D) Rb and Co
E) Fe and Co
12. The representative elements are those with unfilled energy levels in which the "last electron" was added to
A)
an s orbital.
D)
a p or d orbital.
B)
an s or p orbital.
E)
an f orbital.
C)
a d orbital.
13. The Lewis dot symbol for the calcium ion is

A)
: Ca : 2+
B) ٠Ca٠
C)
: Ca : 2+

D) Ca2+
E) Ca
14. A polar covalent bond would form in which one of the following pairs of atoms?
A) Cl -- Cl
B) Si -- Si
C) Ca -- Cl
D) Cr -- Br
E) P -- Cl
15 Which of the elements listed below has the greatest electronegativity?
A) Se
B) Sb
C) K
D) Ga
E) Fe
( 1 x 15 = 15 marks)
16. The Lewis structure for CS2 is:

A)



C  S S


B)



: S  C S :




C)


SCS

D)



E) none of the above
17 . Which one of the following is not isoelectronic with the others: Br–, Rb+, Se2–, Sr2+, Te2–?
A) Br–
B) Rb+
C) Se2–
D) Sr2+
E) Te2–
18. The number of lone electron pairs in the N2 molecule is ___.
A) 1
B) 2
C) 3
D) 4
E) 5

S  C S :

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19. Consider the element with the electron configuration [Xe]6s 24f7. This element is
A)
a representative element
D)
an actinide element
B)
a lanthanide element
E)
a noble gas
C)
a nonmetal
20. Which of the following make an isoelectronic pair: Cl–, O2–, F, Ca2+, Fe3+?
A)
Ca2+ and Fe3+
D)
Cl– and Ca2+
B)
O2– and F
E)
Fe3+ and F
C)
F and Cl–
21. The number of lone electron pairs in the NO2– ion is ___.
A) 4
B) 5
C) 6
D) 7
E) 8
22. Which one of the following compounds does not follow the octet rule?
A) NF3
B) CO2
C) CF4
D) Br2
E) NO
23. The total number of bonding electrons in a molecule of formaldehyde (H2CO) is
A) 3
B) 4
C) 6
D) 8
E) 18
24. The electron dot structure for PCl3 shows
A)
a total of 84 electron dots
B)
three single bonds and 10 lone pairs
C)
two single bonds, one double bond, and 9 lone pairs
D)
one single bond, two double bonds, and 8 lone pairs
E)
three single bonds and one lone pair
25. A ground-state chromium atom has how many unpaired electrons?
A) 1
B) 2
C) 4
D) 5
E) 6
26. The ground-state electron configuration of Cr, Mo, and Ag are exceptions to the Aufbau principle. Which
of the following is the electron configuration for Mo?
A) [Kr]5s14d5
B) [Kr]5s24d4
C) [Xe]6s25d4
D) [Ar]4s24d4
E) [Kr]5s24d6
27. How many electrons in a ground-state zinc atom are in orbitals labeled by ml = –1?
A) 2
B) 6
C) 10
D) 12
E) 18
28. Arrange the following ions in order of decreasing ionic radius: Al 3+, Mg2+, Na+, O2–.
A)
Al3+ > Mg2+ > O2– > Na+
D)
O2– > Al3+ > Mg2+ > Na+
B)
Al3+ > Mg2+ > Na+ > O2–
E)
O2– > Na+ > Mg2+ > Al3+
C)
Na+ > Mg2+ > Al3+ > O2–
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29. Consider the following reaction: 3Li + Z → Li3Z. What is the formula for the compound if we substitute
magnesium for lithium?
A) MgZ
B) Mg2Z
C) MgZ2
D) Mg3Z
E) Mg3Z2
30. What is total number of lone pairs in the best Lewis structure for SOF 4 that exceeds the octet rule (S is the
central atom all the other atoms are connected to it )?
A) 0
B) 2
C) 14
D) 15
E) 16
( 2 x 15 = 30 marks )
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SECTION B
Answer all questions in the space provided.
1. What happen to the atomic radius as we go down the group from top to bottom and across the
period from left to right. Give a brief explanation for the trend that you have described.
( 6 marks )
2. Write the full set of quantum numbers (n, l, ml and ms ) for the following electron
I.
The outermost electron in an Rb atom
II.
The highest energy electron in the ground state B atom.
( 3 x 2 = 6 marks )
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3. Write Lewis structures for FeCl3, NH4+, and NaOH.
( 7 marks )
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4. A sample of vinegar solution contains 5.25 % of acetic acid (CH3COOH). What is the molarity of
the solution if the density of the solution is 1.005 g/mL?
( 10 marks )
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5.
One type of antacid tablet contain MgCO3 and requires 25.50 mL of 0.0955 M HCl to completely
neutralize.. Find the mass of MgCO3 (gram) in that tablet.
MgCO3 + 2 HCl  MgCl2 + CO2 + H2O
( 10 marks )