Transcript Periodic Table Introduction DRB

Introduction
to the
Periodic Table
Init: 9/18/2008 by Daniel R. Barnes
. . . explain the meaning and origin of information
found on the periodic table.
“SWBAT = “Students will be able to”
Atomic number = number of protons
The atomic number defines the element.
If an atom has 11 protons, it’s a sodium atom, guaranteed.
If an atom is a sodium atom, it has 11 protons, guaranteed.
If it hasn’t got 11 protons, it’s not sodium. It’s some other element
=
Natrium
First letter upper case, all others lower case
The symbol and the name don’t always match.
When this happens, it’s probably because the symbol is taken
from the Latin name for the element.
The Roman Empire
“Ferrum” is Latin
for “iron”.
26
Fe
55.85
“Argentum” is Latin
for “silver”.
“Aurum” is Latin
for “gold”.
47
Multi ex
scientia
verba
latina (?)*
Ag
107.87
79
Au
196.97
“Stannum” is Latin
for “tin”.
50
Sn
118.71
* I used the translate function on iGoogle for this. I don’t think it’s trustworthy for English  Latin, to tell you the truth.
You get to use the CST Refence Sheet on all the tests in this
class.
Therefore, you don’t have to memorize all the names and symbols
of every element on the periodic table.
It helps, though.
Although it would surprise Dalton to find this out, not all the atoms
of an element have the same mass.
An atom of an element is guaranteed to have a certain number of
protons (the atomic number of the element).
However, an atom does not have to have a specific number of
neutrons to be in that element.
6
C
carbon
12.01
Therefore, each element occurs as several different isotopes,
each of which has a specific mass number.
Most carbon atoms are carbon-12 atoms, but there are some
carbon-13 atoms, also. That drives the average mass up a bit.
Q1: What is the atomic number of silicon and what does this
mean?
A: The atomic number of silicon is 14, which means all
silicon atoms have 14 protons, and any atom with 14 protons
is a silicon atom.
Q2: What is the difference between Co and CO?
A: “Co” is the symbol for cobalt, a metallic element. “CO” is
the formula for the compound carbon monoxide, a colorless,
odorless, and highly toxic gas.
Q3: Why is the symbol for silver “Ag” instead of “S” or “Si”?
A: “S” was already taken by sulfur, and “Si” was already
taken by silicon. Therefore, scientists based the symbol for
silver on silver’s Latin name, “argentum”.
. . . describe the location of any element on the
periodic table.
“SWBAT = “Students will be able to”
Period one
Period five
Period seven
Period seven
eighteen
Column
Group eighteen
Group six
six
Column
one
Column
Group one
What element is at Row 4, Column 12?
What element is at Period 6, Column 3?
What element is at Row 2, Group 17?
What is the location of manganese?
Period 4, Group 7
What is the location of platinum?
Period 6, Group 10
What is the location of argon?
Period 3, Group 18
. . . relate the position of an element on the
periodic table to its atomic number and atomic
mass.
“SWBAT = “Students will be able to”
Look at what the average atomic masses do as atomic number
increases
Average Atomic Mass/amu
Average Atomic Mass vs. Atomic Number
Atomic Number
http://web.mit.edu/course/3/3.091/www3/pt/pert3.html
52
53
Te
I
127.60 126.90
27
28
Co
Ni
58.93 58.69
18
19
Ar
K
39.95 39.10
There are more
reversals around
here, somewhere,
but don’t worry
about them right
now.
Where
are all
the
light
elements?
The darkened
darker
it is,
the
heavier
it is. in proportion to the
I’ve
each
square
here
atomic are
number
of heavy
the element
in the square
Where
all the
elements?
What happens to average atomic mass as you go to the right?
It gets larger.
What happens to average atomic mass as you go down a
column?
It gets larger.
Q4: What is the relationship between position on the periodic
table and atomic mass/atomic number?
A: Atomic numbers and atomic masses get larger as you go
down or to the right.
User name = hwbrainpop
Ask Mr. Barnes for
password. Can’t give it
here. I post this ppt on
the www. (9/16/2014)
View the “Periodic Table of the Elements” cartoon once you’ve
logged in.
The student account is only good from the hours of 8AM – 4PM.
The
End
18
19
Ar
K
39.95
39.10
Scrap Junkyard
Not part of lecture!
27
28
Co
Ni
58.93
58.69
52
53
Te
I
127.60
126.90