Embed Size (px)
Citation preview
TN Ch 4.6 Date
Title and
Highlight
Topic:
EQ:
Questions:
Write Question out and answer it (in
another color or HIghlight) based on
from what you read.
NOTES:
Now write out the notes from my
website. You may use different color
pens.
Number notes as you go.
Space out your notes so you can add
anything I say to them.
BUT NO HIGHLIGTING,
UNDERLINING, etc
WE WILL DO OUR FOCUS NOTES
TOGETHER
Right Side – NOTES ONLY
TN Ch 4.6
Title and
Highlight
DRAW ANY PICTURES, FIGURES,
AND WRITE OUT ANY PRACTICE
PROBLEMS/QUESTIONS.
WE WILL ANSWER THEM TOGETHER.
LEAVE SPACES SO WE CAN ANSWER
QUES.
LEFT Side – PICTURES, PRACTICE PROBLEMS, ETC
TN Ch 4.6 (part 1)
Topic:The History of the Modern Periodic Table
EQ: How was the first Periodic Table constructed and how is P.T. organized ?
READ Ch 4.6 (pg. 102-106)
Write Questions & Answer Questions #11-13 (notes side)Highlight answer
The periodic table is the most important tool in the chemist’s toolbox!
Why is the Periodic Table important to me?
• You get to use it on every test.
• It organizes lots of information about all the known elements.
Pre-Periodic Table Chemistry …
…was a mess!!!
No organization of elements.
During the nineteenth century, chemists began to categorize the elements according to similarities in their physical and chemical properties.
John Newlands
1838 - 1898
Law of Octaves
In 1863, he suggested that elements be arranged in “octaves” because he noticed (after arranging the elements in order of increasing atomic mass) that certain properties repeated every 8th element.
John Newlands
1838 - 1898 Law of Octaves
FYI – But the science community didn’t like this “repeating pattern” idea....his paper was rejected by the Chemical Society.
Dmitri Mendeleev:Father of the Periodic Table
In 1869 he published a table of the elements.
1834 - 1907
A first look at the periodic tableDmitri Mendeleev organized all of the elements that were known at the time into rows and columns based on their chem/phy similarities and their masses.
Periodic Table•The table is called “periodic” because the pattern of similar properties repeats as you move from period to period.
Lothar Meyer
1830 - 1895
At the same time, he published his own table of the elements organized by increasing atomic mass.
Dmitri MendeleevHOW HIS WORKED…
70 known elements.
Organized rows (periods) by increasing atomic weight.
Put elements in columns (groups) by their properties.
SOME PROBLEMS…
He left blank spaces for undiscovered elements. (Turned out he was right!)
He broke the pattern of increasing atomic weight.
Used his P.T. to predict the physical properties of three elements that were yet unknown.
Problems arose when new elements were discovered.Looking at our modern P.T., can you identify what problems might have caused chemists a headache?
Ar and K
Co and Ni
Te and I
Th and Pa
The fact that Mendeleev’s predictions for Sc, Ga, and Ge were amazingly close to the actual values, his table was generally accepted.
Henry Moseley
1887 - 1915
In 1913, through his work with X-rays, he determined the atomic number of the elements*……elements should be arranged in order of increasing atomic number is known as the periodic law.
Henry MoseleyHis research was halted when theBritish government sent him to serveas a foot soldier in WWI. He waskilled in the fighting in Gallipoli by asniper’s bullet, at the age of 28.Because of this loss, the Britishgovernment later restricted itsscientists to noncombatant dutiesduring WWII.
Glenn T. Seaborg
After co-discovering 10 new elements, in 1944 he moved 28 elements out of the main body of the periodic table to their current location below the main part of the P.T. :Lanthanide and Actinide series.
1912 - 1999
Glenn T. SeaborgHe is the only person to have an element named after him while still alive.
1912 - 1999
Current Periodic Table:
How the P.T. has changed over time?
Current P.T.
Increasing ATOMIC NUMBER!!
Elements in the same group have similar chemical and physical properties!! (Mendeleev did
that on purpose.)
Past P.T.
• Increasing Mass number
(not any more!!!)
• Elements in the same group have similar chemical and physical properties!!
Still the same!!!
TN Ch 4.6 (part 2)
Topic:The organization of the current Periodic Table
EQ: How is the P.T. that we use to today organized ?
READ Ch 4.6 (pg. 102-106)
Write Questions & Answer Questions #14-18 (notes side)Highlight answer
The horizontal rows of the periodic table are called PERIODS (7).
Sketch this
with notes on
right side!!!
The vertical columns are called GROUPS (18), or FAMILIES.
The elements in any grouphave similar physical andchemical properties!
Sketch this
with notes on
right side!!!
1A
2A 3A 4A 5A 6A7A
8A
Elements in the 1A-8A groups are called the representative or main group elements
Sketch this
with notes on
right side!!!
The group B are called the transition elements
Sketch this
with notes on
right side!!!
The elements in the periodic table can be broadly classified as metals,
nonmetals, and metalloids.
Types of Elements
Sketch this
with notes on
right side!!!
3 classes of elements - METALS Located to the _______ of the dark zig-zag line
All Solids!!! Except one – who is it??
shiny surface
Tend to be white/gray/silvery (common exceptions: copper and gold)
◦ ______________ (you can pound it into a flat sheet)
◦ ______________ (you can draw it into a thin wire)
◦good _______________ (heat/electricity)
◦Metals tend to LOSE electrons in chemical changes.
left
malleable
ductile
conductors
3 classes of elements - NONMETALS
Located to the ___________ of the dark zig-zag line.
◦_______ surface
◦ ______________
◦Some are solids and some are gases. Only 1 liquid.
◦good _______________ and poor conductors
◦Nonmetals tend to GAIN electrons in chemical changes.
◦Vary in color (P - red/white, S – yellow, C – black/clear, I – purple, Br – brownish red, etc)
right
dull
brittle
insulators
sulfur
Sketch this
with notes
on right
side!!!
3 classes of elements – METALLOIDS (only 8)
Located on the border of the dark zig-zag line.
◦ the dividing line between metals and nonmetals.
◦ All SOLIDS!
◦ Also called “semimetals”
◦ Behave (chemically) as nonmetals, but look physically & electrical conductivity resembles metals.
◦ Semiconductors – they do conduct some heat/electricity
◦ Used in computers, cell phones, and other modern gadgets.
silicon
Sketch this
with notes
on right
side!!!
Hydrogen
Hydrogen belongs to a family of its own.
Hydrogen is a nonmetal!!!
It’s a diatomic, reactive gas.
Facts
Hydrogen was involved in the explosion of the Hindenberg.
Hydrogen is promising as an alternative fuel source for automobiles
Group 1 - Alkali Metals(not H!!!)
•Very reactive metals (solids) with air and water, always
combined with something else in nature (like in salt).
•Soft enough to cut with a butter knife
Alkali Metal Family
Video Clip
Sketch this
with notes
on right
side!!!
Group 2 - Alkaline Earth Metals
•Reactive metals (solids) that are always
combined with nonmetals in nature.
• Mg and Ca important for our body!!!
•Also, used used in batteries
Sketch this
with notes
on right
side!!!
Groups 3-12: Transition MetalsSketch this
with notes
on right
side!!!
All solids except Mercury
Less reactive harder metals
Includes metals used in jewelry and construction.
Metals used “as metal.”
Transition MetalsGroups 3-12
InnerTransition Metals
Inner Transition elements - also
called the rare-earth elements.
Sketch this
with notes
on right
side!!!
Group 14 - Carbon Family
Elements important to life and computers (Si and Ge).
Carbon is the basis for an entire branch of chemistry.
Sketch this
with notes
on right
side!!!
Group 15 - Nitrogen Family
Nitrogen makes up over 80% of the atmosphere.
Nitrogen and phosphorus are both important in living things.
The red stuff on the tip of matches is phosphorus.
Sketch this
with notes
on right
side!!!
Group 16 - Oxygen Family or Chalcogens
Oxygen is necessary for respiration.
Many things that stink, contain sulfur (rotten eggs, garlic, skunks,etc.)
Sketch this
with notes
on right
side!!!
Group 17 - Halogens
• Very reactive, diatomic,
nonmetals
• Always combined with
other elements in nature .
• Used in some light
fixtures
• Used as disinfectants and
to strengthen teeth. Sketch this
with notes
on right
side!!!
Group 18 - Noble Gases
• VERY unreactive,
monatomic gases
• Don’t form compounds!!!
(These are also called
“Inert gases”)
• Used in lighted “neon”
signs and balloons.
Sketch this
with notes
on right
side!!!
The periodic table with groups highlighted: 1A, alkali metals; 2A, alkaline earth metals; 7A, halogens; and 8A, noble gases.
Sketch this
left side!!!
A
l
k
a
l
i
M
e
t
a
l
s
A
l
k
a
l
I
n
e
E
a
r
t
h
M
e
t
a
l
s
N
o
b
e
l
G
a
s
e
s
H
a
l
o
g
e
n
s
Transition Metals
Inner Transition Metals
Representative Elements
Transition Elements
Rep
resen
tativ
e E
lem
en
ts
METALS
Periods
Gro
up
s
Nonmetals
QUESTIONS
TN Ch 4.7
Topic: Ions
EQ: How is the atom affected by ions?
READ Ch 4.7 (pg. 106-108)
Write Questions & Answer Questions #19-21 (notes side)Highlight answer
Let’s refresh our memory about the atom and isotopes….
Atomic number (Z).
Protons determines the identity of the element.
A# = p+ = e- (atoms are
neutral)
The Mass Number (A),
(rounded to the nearest
integer)
Mass# = p+ + no
# of neutrons = mass # – p+
Isotopes: When the Number of Neutrons & Mass # Varies
All atoms of an element have the same # of protons.
Atoms with the same # of protons but different # of neutrons (this causes the mass # to also change) are called isotopes.
EXAMPLE OF AN ISOTOPE
Cl35
17 Cl37
17
20 NEUTRONS
ATOMIC MASS
18 NEUTRONS
ATOMIC NUMBER
So…
Atomic# = p+ = e-
(if atom is neutral)HOWEVER…..what if the atom is not neutral?
Electrons
•Electrons can be lost or gained = Chemical
Reaction, which make up more than 99% of
all rxns in life)
• When electrons are lost or gained, IONS are
formed.
•And electrons won’t equal protons no
more!!! Atomic# = p+ = e-
•
Ions: Cations vs. Anions
Positive ions (lose e-) are called cations.
Negative ions (gain e-) are called anions.
The charge of an ion is shown in the upper right corner of the symbol.
Ion Symbol Notation
XMass
number
Atomic
numberSubscript →
Superscript →+2
Lost 2 e-
So… how do you know how many electrons atoms will lose or gain to form an ion?
Ions and the Periodic Table
The # associated with the A groups above each representative (main-group) column on the P.T. —1 through 8—gives the number of valence electrons (electrons on the far outside of the atom – these e- are the ones used first for chemical bonding!!!)
The key to predicting the charge acquired by an element is its position in the periodic table relative to the noble gases. Why noble gases?
Elements that form predictable ions
If an atom has a charge associate with it, it is an ION:
88 2
38 Sr
How many protons, neutrons, and electrons are there?
Important: If an atom has a negative charge = an anion. If an atom has a positive charge = a cation.
Review Questions
1. Given
Determine the number of protons, neutrons and electrons in this atom.
356
26 Fe
Left Side
Review Questions
2.
Determine the number of protons, neutrons and electrons in this atom.
232
16
S
Left side!!!
How many protons, neutrons & electrons are there in the following?
3. Cl-38 6. 35Cl-1
4. Br-80 7. 32S-2
5. N-14 8. 56Fe+3
Left side!!!
