WorksheetsAtomic Structure and Properties 1
Total questions: 25
Worksheet time: 31mins
Name
Class
Date
1.
What is the mass in grams of 5.90 mol C8H18?
a)
.0512 g
b)
19.4 g
c)
673 g
d)
389 g
2.
How many moles are present in 32.3 grams of carbon dioxide (CO2)?
a)
44.01 moles
b)
1421.52 moles
c)
32.3 moles
d)
0.73 moles
3.
What is the mass of 2.50 mol of oxygen gas O2?
a)
40 g
b)
80 g
c)
16 g
d)
32 g
4.
How many water molecules are in 5.2 moles of water?
a)
6.02 x 1023
b)
5.2
c)
3.1304 x 1024
d)
8.638 x 10-24
5.
What do the peaks on the mass spectrum represent?
a)
anions
b)
different isotopes
c)
atoms with differing numbers of electrons
d)
numbers of electrons
6.
What do the heights of the peaks represent in the mass spectrum?
a)
number of isotopes
b)
relative abundance of each isotope
c)
average atomic mass
d)
charge:mass ratio
7.
How many isotopes are shown in this mass spectrum?
a)
1
b)
84
c)
86
d)
4
8.
What is the average atomic mass for this element?
a)
10 amu
b)
10.8 amu
c)
19.9 amu
d)
11 amu
9.
How many stable isotopes are represented on the mass spectrum?
a)
1
b)
2
c)
3
d)
4
e)
5
10.
What is the average atomic mass based on the mass spectrum data?
a)
24.32 amu
b)
22.99 amu
c)
30.84 amu
d)
25.00 amu
11.
To which element does this mass spectrum belong?
a)
Na
b)
Mg
c)
Al
d)
Ne
12.
What element's mass spectrum is represented below?
a)
Re
b)
As
c)
W
d)
Mo
13.
Investigate the mass spectra attached. Which peak is the most abundant?
a)
90
b)
91
c)
94
d)
92
e)
96
14.
In which compound is the percent composition by mass of Cl equal to 42%?
a)
HClO (gram formula mass = 52 g/mol)
b)
HClO2 (gram formula mass = 68 g/mol)
c)
HClO3 (gram formula mass = 84 g/mol)
d)
HClO4 (gram formula mass = 100 g/mol)
15.
What is the percent composition by mass of sulfur in the compound MgSO4 (gram formula mass = 120 g/mol)?
a)
20%
b)
27%
c)
46%
d)
53%
16.
How many molecules are in 2.5 mol of NaCl?
a)
1.5 x 1024 molecules
b)
1.5 molecules
c)
4.15 molecules
d)
1.5 x 1023 molecules
17.
What is the percent composition by mass of sulfur (S) in the compound MgSO4?
a)
20.22%
b)
19.85%
c)
26.64%
d)
28.64%
18.
Which pair has the same empirical formula?
a)
NaCrO4 and Na2Cr2O7
b)
C2H4O2 and C6H12O6
c)
C3H6O3 and C2H6O2
d)
CH4 and C2H6
19.
A compound consists of 72.2% magnesium(Mg) and 27.8% nitrogen(N) by mass. What is the empirical formula?
a)
Mg4N3
b)
MgN2
c)
Mg3N2
d)
MgN
20.
You are given the following percentages: 40.05% S and 59.95% O. Find the empirical formula for these elements.
a)
SO
b)
SO2
c)
SO3
d)
SO4
21.
What is the empirical formula if you have 81.82% carbon and 18.18% hydrogen?
a)
C3H8
b)
CH4
c)
C2H2
d)
C4H10
22.
What is the percentage of iron in iron(III)oxide?
a)
30%
b)
70%
c)
40%
d)
60%
23.
What is the molecular formula if the empirical formula is CH2O and the molecular molar mass is 180.18?
a)
CH2O
b)
C2H4O2
c)
C4H8O4
d)
C6H12O6
24.
Glycerol has a molar mass of 92.09g/mol. Its percent composition is: 39.12% C, 8.75% H, and 51.12% O. What is the molecular formula for glycerol?
a)
C2H3O2
b)
CH2O
c)
C2H4O2
d)
C3H8O3
25.
What is the molecular formula if the empirical formula is C2H5 and the molecular molar mass is 58.14 g/mol?
a)
C2H5
b)
C4H10
c)
C1H2.5
d)
C4H8
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