Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Counting Atoms Worksheet # 1
1. Determine the subatomic particles in each of the following::
p+
27
e-
n°
Atomic #
Mass #
n°
Atomic #
Mass #
Al
Br
Fe
Ca+2
O-2
2. Complete the following table:
p+
e-
K+1
40
12
12
36
-1
53
91
10
19
3. Carbon consists of 98.89% 12C (12.00000), and 1.110% 13C (13.00335). Calculate the atomic weight of
carbon to four significant figures.
4. Gallium consists of two natural isotopes, 69Ga (68.9257) makes up 60.40% of the total. Calculate the %
abundance and the mass of the other isotope.
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
5. Calculate the molar mass of
H2SO4
Cu(NO3) • H2O
C3H5(OH)3
6. Convert each of the following using the factor-label method:
0.15 moles of Cu to atoms
75.0 g of H2SO4 to moles
2.55 x 1012 atoms of Ca to grams
10.0 g of Na to atoms
0.100 moles of NaOH to grams
7. How many helium atoms would weigh the same number of grams as 6.00 x 10 15 carbon atoms?
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Worksheet # 2
1. Label the following chemicals as either elements or compounds.
C
Co
CO
NaCl
F2
CaO
F2
CaO
2. Label the following chemicals as atoms, molecules, or formula units.
C
Co
CO
NaCl
3. Iron consists of four natural isotopes:
%
isotope
exact isotopic mass
5.82
54Fe
53.9696
91.66
56Fe
55.9349
2.19
57Fe
56.9354
0.33
58Fe
57.9333
Calculate the atomic weight of iron to four significant figures.
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
3. Neon consists of three natural isotopes:
%
isotope
exact isotopic mass
90.92
20Ne
19.99244
0.257
21Ne
20.99395
Calculate the (a) % abundance, (b) exact isotopic mass, and (c) mass number of the third isotope.
4. Titanium consists of five natural isotopes:
%
isotope
exact isotopic mass
7.93
46Ti
45.95263
7.28
47Ti
46.9518
5.51
49Ti
48.94787
5.34
50Ti
49.9448
Calculate the (a) % abundance, (b) exact isotopic mass, and(c) mass number of the fifth isotope.
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Worksheet # 3
Convert each of the following:
1. 1.00 mol of Al to grams
2. 1.00 mol of Fe to grams
3. 6.022 x 1023 atoms of Ag to grams
4. 4.25 mol of Li to grams
5. 8.075 mol Au to grams
6. 2.57 x 108 mol of S to grams
7. 1.75 x 10-6 mol of Hg to grams
8. 11.5 g of Na to atoms
9. 3.25 x 105 g of Pb to atoms
10. 0.00750 g of Ag to atoms
11. 1.00 x 10-10 g of Au to atoms
12. This element has a mass # of 197 and a neutron # of 118. How many protons and electrons does this
element have? What element is this?
13. Fe+3
Neutrons =
Protons =
Electrons =
14. P-3
Neutrons =
Protons =
Electrons =
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Worksheet # 4 –Conversion Worksheet
Show work Complete on a separate sheet of looseleaf.
I. Convert to moles:
VI. Convert to moles:
1. 12.04 x 1023 atoms He
21. 6.0 x 1023 molecules CO2
2. 3.01 x 1023 atoms Cu
22. 34 grams NH3
3. 1 atom S
23. 9.00 grams H2SO4
4. 98.9 grams Na
24. 1.00 grams NaCl
II. Convert to mass in grams:
VII. Convert to mass in grams:
5. 10.0 moles Na
25. 5.0 moles NH3
6. 2.20 moles Sn
26. .00200 mole Na2SO4
7. .0003000 mole Au
8. 1.00 x 107 moles B
VIII. Convert to # of molecules
27. 2.0 moles CO2
III. Convert to # of atoms:
28. 1.00 x 10-3 mole CO
9. 3.00 moles Ar
10. 8.50 moles Fe
IX. Convert to # of molecules
11. .00100 mole Na
29. 22 grams CO2
12. 1.0 x
10-5
mole Al
X. Convert to mass in grams
IV. Convert to mass in grams:
30. 3.01 x 1023 molecules SO2
13. 6.02 x 1023 atoms Ca
14. 1.204 x 1023 atoms Bi
15. 1000 atoms Al
16. 1 atom Na
V. Convert to # of atoms:
17. 540 grams Al
18. 294 grams Au
19. 2000 grams Mg
20. 1.00 grams Li
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Worksheet # 5 - Review
Fill in the gaps in the tables below:
1.
Symbol
39
+2
K
p+
25
n°
30
e-
-2
82
82
54
Mass #
18
33
207
2.
Symbol
70
-2
Ga
P+
23
n°
28
eMass #
+2
45
36
136
81
197
Atomic #
86
3. Vanadium consists of two isotopes: 50V (49.9472) is 0.24% and 51V (50.9440) is 99.76%. Calculate the
atomic weight of Vanadium.
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Worksheet # 5 – cont’d
4. Chromium consists of four isotopes. 50Cr (49.9461) is 4.31%, 52Cr (51.9405) is 83.76%, 54Cr (53.9389)
is 2.38% Calculate the % abundance and exact isotopic mass of the other isotope.
5. Calculate the molar mass of:
(a) BaCl2
(b) (NH4)SO4
(c) Mn3(PO4)2 • 4H2O
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Accelerated Chemistry
Atomic Structure and Mole Conversions
Chemist: ____________________
Worksheet # 5 – cont’d
6. Convert each of the following using factor-label method:
(a) 3.85 grams of FeSO3 to moles
(b) 2.78 x 10-5 moles of P2S5 to grams
(c) 4.702 x 1047 atoms of Au to moles
(d) 4.140 moles of NaH2PO4 to molecules
(e) 5.31 x 1028 molecules of Mg(OH)2 to grams
(f) 152.1 grams of HC2H3O2 to molecules
7. Explain why the mass of a chlorine atom really isn’t 35.45 amu.
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