Elements and Symbols
Quiz Study Guide
Latin Words – know these words
◦ Micro – small
◦ Macro – large
◦ Iso – same
◦ Topes – place
◦ Poly – many
◦ Mono – one
Saccharum – sugar
◦ Ose – having a specified quality
◦ Co – together
◦ Ad – to others
◦ Pole – end of an axis
Reading a Periodic Table
How to read an Isotopic Symbol
A
Z
X
C
X = Element Symbol
A = Mass Number
Z = Atomic Number
C = Net Charge
Typical Isotopyic Symbol
19
9
F
Flourine Isotopyic Symbol
A = Mass Number: The mass number is the weight of an element. It is found by adding the protons and neutrons
together. A simple equation can be used to find the mass number. P + N = Mass Number
Z = Atomic Number: The atomic number is simply the number of protons.
C = Net Charge: Net charge tells us whether or not an atom has a positive charge or a negative charge. You can find the
charge by adding the protons and electrons together. A simple equation can be used to find the net charge. P + (-e) = net
charge. Remember: protons are always positive numbers and electrons are always negative.
Taking apart an Isotopic Symbol Walkthrough
Answer:
P = 11
N = 12
E = 10
Electrons are
always negative
numbers, so its not
necessary to write
put a negative in
your answer.
Step 1: Find your atomic number
to find the number of protons.
Mass Number
Atomic Number
Neutrons:
P + N = Mass Number
11 + X = 23
-11
-11
0
12
X = 12 Neutrons
23
11
+
Na
Electrons
P + (-e) = Net Charge
11 + X = 1
-11
-11
0
-10
X = -10 electrons
Step 2: Use your mass number
formula to find your neutrons.
P + N = Mass Number
Step 3: Use your net charge
formula to find your electrons.
P + (-e) = Net Charge
Taking apart an Isotopic Symbol: Practice
Answer:
P = 11
N = 12
E = 10
Electrons are
always negative
numbers, so its not
necessary to write
put a negative in
your answer.
Step 1: Find your atomic number
to find the number of protons.
Mass Number
Atomic Number
Neutrons:
P + N = Mass Number
11
5
B
-3
Electrons
P + (-e) = Net Charge
Step 2: Use your mass number
formula to find your neutrons.
P + N = Mass Number
Step 3: Use your net charge
formula to find your electrons.
P + (-e) = Net Charge
Taking apart an Isotopic Symbol: Answer
Answer:
P=5
N=6
E=8
Electrons are
always negative
numbers, so its not
necessary to write
put a negative in
your answer.
Step 1: Find your atomic number
to find the number of protons.
Mass Number
Atomic Number
Neutrons:
P + N = Mass Number
5 + X = 11
-5
-5
0
6
X = 6 Neutrons
11
5
B
-3
Electrons
P + (-e) = Net Charge
5 + X = -3
-5
-5
0
-8
X = 8 electrons
Step 2: Use your mass number
formula to find your neutrons.
P + N = Mass Number
Step 3: Use your net charge
formula to find your electrons.
P + (-e) = Net Charge
Building an Isotopic Symbol: Walkthrough
A
Z
X
C
A bromine atom with 45 neutrons and 38 electrons.
Typical Isotopyic Symbol
80
35
Br
Answer
-3
*There are many ways to find your protons. In this case
you will look up Bromine on your periodic table to find the
atomic number.
Mass Number = P + N
X = 35 + 45
X = 80
Net Charge = P + (-e)
X = 35 + (-38)
X = -3
Step 1: Find and write your symbol using
the number of protons*.
Step 2: write the number of protons on the
left bottom side of your symbol.
Step 3: Find your mass number by adding
your protons and neutrons together.
Step 4: write your mass number above
your proton number on the upper left side
of your symbol.
Step 5: Find your electrons using
P+ e = net charge
Step 6: Write your net charge on the upper
right hand side of your symbol.
Building an Isotopic Symbol: Walkthrough
Mass Number
A
Z
Atomic Number
X
Net Charge
C
An atom that has 59 protons and 82 neutrons.
Typical Isotopyic Symbol
*There are many ways to find your protons. In this case
you will look up Bromine on your periodic table to find the
atomic number.
Mass Number = P + N
80
35
Br
Answer
Step 1: Find and write your symbol using
the number of protons*.
Step 2: write the number of protons on the
left bottom side of your symbol.
Step 3: Find your mass number by adding
your protons and neutrons together.
Step 4: write your mass number above
your proton number on the upper left side
of your symbol.
-3
Net Charge = P + (-e)
X = 35 + (-38)
X = -3
Step 5: Find your electrons using
P+ e = net charge
Step 6: Write your net charge on the upper
right hand side of your symbol.
Building an Isotopic Symbol: Practice
A
Z
X
C
An isotope that has 59 protons and 82
neutrons. And 55 electrons
*There are many ways to find your protons. In this case
the atomic number 59 to find your symbol.
Typical Isotopyic Symbol
Mass Number = P + N
Step 1: Find and write your symbol using
the number of protons*.
Step 2: write the number of protons on the
left bottom side of your symbol.
Step 3: Find your mass number by adding
your protons and neutrons together.
Step 4: write your mass number above
your proton number on the upper left side
of your symbol.
Net Charge = P + (-e)
Answer
Step 5: Find your electrons using
P+ e = net charge
Step 6: Write your net charge on the upper
right hand side of your symbol.
Building an Isotopic Symbol: Practice
A
Z
X
C
An isotope that has 59 protons and 82
neutrons. And 55 electrons
*There are many ways to find your protons. In this case
the atomic number 59 to find your symbol.
Typical Isotopyic Symbol
Mass Number = P + N
X = 59 + 82
X = 141
+4
141
59
Pr
Answer
Net Charge = P + (-e)
X = 59 + (-55)
X = +4
Step 1: Find and write your symbol using
the number of protons*.
Step 2: write the number of protons on the
left bottom side of your symbol.
Step 3: Find your mass number by adding
your protons and neutrons together.
Step 4: write your mass number above
your proton number on the upper left side
of your symbol.
Step 5: Find your electrons using
P+ e = net charge
Step 6: Write your net charge on the upper
right hand side of your symbol.
Balanced Atoms, Isotopes and Ions:
Know the difference!
Balanced Atom = Equal Number of Protons, Neutrons and
Electrons
Isotopes = An atom that has more or less neutrons than
protons
Ion = An atom that has more or less electrons than protons.
◦ Anion: More Electrons than Protons
◦ Cation: Less Electrons than Protons
Mass Number and Atomic Mass
Mass Number = The weight of one atom or isotope of an element. This weight is found by
adding the Protons and Neutrons in an atom or isotope together. P + N = Mass Number
Atomic Mass = The average weight of all atoms and isotopes of an element. This average weight
is found by finding the percent abundance of each isotope and then multiplying the weight of
the isotope by the percent abundance. Add up the sums for each isotope to get the atomic
mass. You can find the atomic mass on the periodic table of elements.