South Pasadena • Chemistry
Name
Period
Date
2 · Elements and Compounds
STATION 1
•
THE ATOM
For each of the following, indicate whether it describes the proton (P), neutron (N), or electron (E). Each
description may refer to one or more subatomic particle.
PN Determines the mass of the atom
E
P
Has a mass of 1/1800th amu
Carries a +1 charge
PN Has a mass of 1 amu
PN Makes up the nucleus
P
Determines the identity of the atom
E
Is changed to form different ions
E
Determines the size of the atom
N
Has no charge
N
Is changed to form different isotopes.
2 · Elements and Compounds
STATION 2
Complete the following table:
Atomic
Isotope
Number
• ISOTOPIC NOTATION
Mass
Number
Number of
Protons
Number of
neutrons
Number of
electrons
Net Charge
20
44
20
24
20
0
Al
13
27
13
14
13
0
Fe2+
26
57
26
31
24
+2
53
131
53
78
54
–1
44
Ca
27
57
131 −
I
2 · Elements and Compounds
STATION 3
•
MORE ISOTOPIC NOTATION
Write the isotopic notation the following atoms:
 50 protons, 68 neutrons, 46 electrons
118
Sn4+

80 protons, 118 neutrons, 79 electrons
198
Hg+

15 protons, 16 neutrons, 18 electrons
31 3−
P

28 protons, 34 neutrons, 28 electrons
62
Ni
Find the number of protons, neutrons, and electrons for the following atoms:
 27Al3+
 129Xe
13 protons, 14 neutrons, 10 electrons
54 protons, 75 neutrons, 54 electrons

18
O2–
8 protons, 10 neutrons, 10 electrons

53
Cr3+
24 protons, 29 neutrons, 21 electrons
2 · Elements and Compounds
STATION 4
• CLASSIFYING MATTER
For each of the following, indicate whether it describes a metal (M), semi-metal (SM), or non-metal (NM).
M
1. Shiny and ductile
NM
6. Argon, Ar, is an example
NM
2. Poor conductors
SM
7. Also called semiconductors
M
3. Magnesium, Mg, is an example
SM
8. Silicon, Si, is an example
NM
4. Brittle
M
9. Good conductors
SM
5. Arsenic, As, is an example
NM
10. Hydrogen, H, is an example
2 · Elements and Compounds
STATION 5
What does each of these parts represent?
•
PERIODIC TABLE
Atomic number (# of protons)
6
C
12.011
Element symbol
Atomic Mass
Identify each part of the periodic table:
Transition Metals
List the seven diatomic elements:
H2, N2, O2, F2, Cl2, Br2, I2
Noble Gases
SemiMetals
Halogens
Other Metals
Other NonMetals
Alkaline Earth Metals
Alkali Metals
H
List the two liquids at room temperature:
Br2, Hg
2 · Elements and Compounds
STATION 6
Classify each sample:
 Bromine liquid, Br2
 Ozone, O3
 Salt, NaCl
 Solid gold, Au
 Sugar, C6H12O6
•
Atom | Molecule
Atom | Molecule
Atom | Molecule
Atom | Molecule
Atom | Molecule
TYPES
OF
COMPOUNDS
Element | Compound
Element | Compound
Element | Compound
Element | Compound
Element | Compound
Identify each of the following with A = acid, C = covalent, I = ionic, or O = organic.
I
Na2S
O
C2H4
A
H2CO3
O
C4H9OH
I
Ca(NO2)2
C
P4O10
C
NO2
I
Al2(SO4)3
A
HClO4
2 · Elements and Compounds
STATION 7
•
MOLECULAR MASS/%COMPOSITION
Calculate the molecular masses of Na2SO3 and Ca(NO3)2.
Na: 2 × 22.99 = 45.98
Ca: 1 × 40.08 = 40.08
S: 1 × 32.07 = 32.07
N: 2 × 14.01 = 28.02
O: 3 × 16.00 = 48.00
O: 6 × 16.00 = 96.00
Molecular Mass: 126.05 amu/molecule
Molecular mass: 164.10 amu/molecule
Calculate the percent composition of each element in the following compounds.
Na2SO3
Ca(NO3)2
%Na =
%Ca =
45.98
× 100%
126.05
= 36.48%
40.08
× 100%
164.10
= 24.42%
%S =
%N =
32.07
× 100%
126.05
= 25.44%
28.02
× 100%
164.10
= 17.07%
%O =
%O =
48.00
× 100%
126.05
= 38.08%
96.00
× 100%
164.10
= 58.50%
2 · Elements and Compounds
STATION 8
Show your work for each question.
What is the molar mass of propane, C3H8?
3(12.01) + 8(1.008) = 44.07 g/mol
How many moles are in a sample of 4.55 × 1024 molecules of C3H8?
1 mol C3H8

4.55 × 1024 molecules C3H8 
6.022 × 1023 molecules C3H8 = 7.56 mol C3H8
What is the mass of a 15.2-L sample of C3H8 at STP?
1 mol C3H8  44.07 g C3H8
15.2 L C3H8 
= 29.9 g
22.4
L C3H8  1 mol C3H8 

•
MOLES
2 · Elements and Compounds
STATION 9
Show your work for each question.
What is the molar mass of ozone, O3?
3(16.00) = 48.00 g/mol
How many moles O3 occupy 15.6 L at STP?
1 mol O3 
15.6 L O3 
22.4 L O3 = 0.696 mol O3
How many molecules of O3 are in a 61.9 g sample?
1 mol O3  6.022 × 1023 molecules O3
23
61.9 g O3 
1 mol O3
48.00 g O3 
 = 7.77 × 10 molecules
•
MORE MOLES