Download Unit 3 Notes only

Matter and Atoms
1. ____________ are
smallest parts of
matter.
ATOMS
2. The positively
charged center of an
atom is called a
____________
NUCLEUS
3. The nucleus is
surrounded by
negatively charged
particles called
_________.
ELECTRONS
4. The three particles
that make up an atom
are:
PROTONS,
NEUTRONS and
ELECTRONS
Matter and Atoms
**These particles are called SUBATOMIC
PARTICLES**
Subatomic
Particle
Mass of
Particle
Charge
Location in
the atom
Proton
1
+
In Nucleus
Neutron
1
None
In Nucleus
Electron
0
-
Outside
Nucleus
Matter and Atoms
6. What is the charge of the NUCLEUS in at
atom? (circle one)
POSITIVE
7. Label the following diagram of an atom:
Electron
Nucleus
(outside nucleus)
(central part)
Proton
(makes up nucleus)
Neutron
(makes up nucleus)
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Counting Atoms
1. What does the atomic number of the atom tell
you?

Number of protons in nucleus

Number of electrons outside nucleus
a.
How many protons and electrons
does the element copper have?
29
b.
How many protons and electrons does
the element iron have?
26
Counting Atoms
*** THE NUMBER OF PROTONS IN THE
NUCLEUS OF AN ATOM AND THE
NUMBER OF ELECTRONS AROUND THE
NUCLEUS DETERMINES WHAT THE
ELEMENT IS.
***FOR EXAMPLE, THE ELEMENT
HYDROGEN AND ONLY THE ELEMENT
HYDROGEN WILL HAVE 1 PROTON AND
1 ELECTRON
Counting Atoms
2. If the element Carbon (C) has the atomic
number of 6, how many protons does it
have ____________. How many electrons
____________.
6 protons
6 electrons
THE NUMBER OF ELECTRONS = THE
NUMBER OF PROTONS
Counting Atoms
3.
Refer to your periodic table.
2
He
4.002
Atomic Number
Symbol
Atomic Mass
Using the information above and your periodic table to answer the
following questions:
a. What is the atomic number of Aluminum (Al)?
13
b. How many protons does (Ne) have?
10
c. How many electrons does Helium (He) have?
2
d. What is the atomic number of Einsteinium (Es)?
99
e. How many protons does Calcium (Ca) have?
20
f. How many electrons does Phosphorus (P) have?
15
Agenda for 11/14/16
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
Turn in Yellow Packet #2
Periodic Table Puns
The Atom: A Cloudy View Notes
The Atoms Family worksheet
HW – Finish Atom’s Family Worksheet
 Atomic Structure Quiz on Friday
 30 Element Quiz next Tuesday
The Atom: A Cloudy View
*An
electron cloud is a region where
electrons are most probably found.
The electron cloud surrounds the
nucleus of an atom.
https://www.youtube.com/watch?v=lr
9WZP9gjhM
Energy Levels and Electrons
1.
2.
3.
Within the electron cloud,
electrons are at various
distances from the nucleus.
These are called energy
levels.
Electrons close to the nucleus
have LOW energy
Electrons farther away from
the nucleus have HIGHER
energy.
Electrons with LOW energy
Electrons with HIGHER energy
4. What are the MAXIMUM
electrons in each energy level?
a. 1st energy level
2 electrons
b. 2nd energy level
8 electrons
c. 3rd energy level
18 electrons
d. 4th energy level
32 electrons
e. 5th energy level
32 electrons
f. 6th energy level
18 electrons
g. 7th energy level
8 electrons
h. 8th energy level
2 electrons
Mass of Atoms
**ATOMIC MASS: the average mass of all the
isotopes of that particular element.
2
He
4.002
Atomic Mass
**The atomic mass of Helium (He) is 4.002. If
you round it to the nearest whole number
that would be the MASS NUMBER. So the
mass number of Helium is 4.
Use your periodic table to determine
the following:
1. What is the atomic mass of Oxygen (O)?
15.994
What is the mass number of Oxygen (O)?
16
2. What is the atomic mass of Nitrogen (N)?
14.0067
What is the mass number of Nitrogen (N)?
14
Mass Number
1. The sum of the number of protons
(atomic number) and the number of
neutrons in an atom is called the MASS
NUMBER.
OR
Mass Number = Number of Protons +
Number of Neutrons
2. What is the mass number of an
element with 8 protons and 6
neutrons?
14
3. How many neutrons are in an atom
with a mass number of 19 and 9
protons?
10
Use your periodic table for the
following:
4. What is the atomic number of Magnesium (Mg)?
12
5. What is the mass number of Mg?
24
6. How many protons are in Mg?
12
7. How many neutrons are in Mg?
12
8. How many electrons are in Mg?
12
Isotopes of an Element
1. Isotope - atoms of the same element that have
different numbers of neutrons.
2. Why isn’t the atomic mass of an element a whole
number?
It is the average mass of an element of its
isotopes.
3. How are isotopes of an element alike and how
are they different?
Alike - The element name, symbol and atomic
number are the same.
Different - The number of neutrons and mass
number are different.
Isotopes of an Element




Whenever you have an element that has at least
two different values of neutrons, you have what
is called an ISOTOPE.
Example of isotope:
Potassium (K) has the atomic number of 19.
This will never change. However, there are
situations where Potassium could have an
atomic mass of 39.10 (mass number of 39 = 19
protons and 20 neutrons).
Potassium could also have an atomic mass of
39.72 (mass number of 40 = 19 protons and 21
neutrons).
Isotope or Different Element?
 If comparing 2 substances and they have
the same # of protons and different number
of neutrons = isotopes
 If comparing 2 substances and they have a
different amount of protons and
same/different # of neutrons = different
element
Isotopes or Different Elements?
Identify as isotopes or different elements and
name of element(s).
Element A has 34 protons and 45 neutrons.
Element B has 34 protons and 46 neutrons.
Answer: isotopes (Se – Selenium)
Element C has 2 electrons and 7 neutrons.
Element D has 3 electrons and 9 neutrons.
Answer: different elements (He – Helium and Li – Lithium)
Element E has an atomic number or 54 and 67 neutrons.
Element F has an atomic number of 54 and 69 neutrons.
Answer: isotopes (Xe – Xenon)
Atomic Structure Sheet #1
 1) Explain how the following terms are related
– Atomic number and proton – the atomic number
tells you how many protons there are in an
element
– Isotope and neutron – isotopes are based on
different number of neutrons
– Electrons and energy levels – electrons are
found in energy levels. Energy levels are used to
predict the location of electrons
– Mass number and isotope – the mass number is
found by averaging all of the isotopes of an
element
 2) Find the missing numbers.
Element
Atomic #
Mass #
Protons
Neutrons
Electrons
Iron
26
56
26
30
26
Sulfur
16
32
16
16
16
Carbon
6
12
6
6
6
Fluorine
9
19
9
10
9
Calcium
20
40
20
20
20
Nitrogen
7
14
7
7
7
Copper
29
64
29
35
29
Sodium
11
23
11
12
11
Mercury
80
201
80
121
80
Silver
47
108
47
61
47
 3) Isotopes or Different Elements?
 A. Element D has 6 protons and 7 neutrons.
Element F has 7 protons and 7 neutrons
– Different Elements
 B. Element J has 27 protons and 32
neutrons. Element K has 27 protons and 33
neutrons.
– Isotopes
 C. Element T has atomic # 20 and atomic
mass 40. Element Z has atomic #20 and
atomic mass 41.
– Isotopes
 D. Element W has 8 protons and 8 neutrons.
Element X has 7 protons and 8 neutrons.
– Different elements
Niels Bohr (1885-1962)
 Danish physicist
 Contributed to our understanding of
the structure of properties of atoms.
 He won the 1922 Nobel Prize for
physics, mainly for his work on
atomic structure.
 During World War II, Bohr fled
Copenhagen to escape the Nazis.
He traveled to Los Alamos, New
Mexico to advise the scientists
developing the first atomic bomb.
 He returned to Copenhagen after
the war and later promoted the
peaceful use of atomic energy.
Bohr Diagrams
1) Find your element on the periodic table.
2) Determine the number of electrons – it is
the same as the atomic number.
3) This is how many electrons you will draw.
Bohr Diagrams
 Find out which period
(row) your element is
in.
 Elements in the 1st
period have one
energy level.
 Elements in the 2nd
period have two
energy levels, and so
on.
Bohr Diagrams
C
1) Draw a nucleus with
the element symbol
inside.
2) Carbon is in the 2nd
period, so it has two
energy levels, or
shells.
3) Draw the shells
around the nucleus.
Bohr Diagrams
C
1) Add the electrons.
2) Carbon has 6
electrons.
3) The first shell can
only hold 2 electrons.
Bohr Diagrams
C
1) Since you have 2
electrons already
drawn, you need to
add 4 more.
2) These go in the 2nd
shell.
3) Add one at a time starting on the right
side and going
counter clock-wise.
Bohr Diagrams
C
1) Check your work.
2) You should have 6
total electrons for
Carbon.
3) Only two electrons
can fit in the 1st shell.
4) The 2nd shell can hold
up to 8 electrons.
5) The 3rd shell can hold
18, but the elements
in the first few periods
only use 8 electrons.
Periodic Table Classification
How Lady Gaga Writes Her
Music…
BY:
Can Anyone Else Spell Their
Name Using Periodic Table?
Dimitri Mendeleev
 Mendeleev set out to identify a pattern in the
elements.
 He made an important observation that some
elements have similar chemical and physical
properties.
– densities, melting points, color, atomic mass, etc.
 Mendeleev's hunch was that these similarities
were the key to unlocking the hidden pattern of
the elements.
 1869 created the first Periodic Table of Elements
Long version of Periodic Table
 Periodic - means that there is a repeating
pattern
– the properties of the elements repeat with
each row, or period, of the table
 The elements are arranged in rows and
columns
– Rows are also called periods
– Columns are also called groups or families
Groups or Families
 Groups or families are the18 Vertical
columns
 Elements in the same group or family have
similar but not identical characteristics.
 Groups or families have elements with
similar characteristics.
 Group 1 elements all react violently with
water.
http://www.youtube.com/watch?v=ODf_sPexS2Q
http://www.youtube.com/watch?v=Jy1DC6Euqj4
Periods
 Elements in a period are not alike in
properties
 Atomic number and atomic mass increases
from left to right
What periods are the following in?
I
–5
H
–1
 Au
–6
 Li
–2
What group are the following in?
 Cu
– 11
N
– 15
 He
– 18
 Ti
–4
 What element is in group 2 period 4?
– Calcium (Ca)
 What element is in group 18 period 4?
– Krypton (Kr)
 What element is in group 10 period 6?
– Platinum (Pt)
Periodic Table Classification
Elements are grouped according to
metallic characteristics:
METALS
Physical properties:
1. High Luster (shininess).
2. Malleable (able to hammer into thin
sheets).
3. Ductile (able to make into wires).
4. Good conductors of heat and electricity.
Location:
Left side of the stairs (except H).
Most metallic in bottom left (Fr) and
least metallic in top right (Al).
2/3 of all elements are METALS!!
Periodic Table
NON-METALS
Physical Properties:
1. Little or no luster.
2. Not malleable.
3. Not ductile.
4. Good insulators; doesn’t conduct electricity or
heat well.
5. Brittle.
Location:
Right side of the stairs.
Most non-metallic is (O) and least nonmetallic is (Se).
Periodic Table
METALLOIDS
Physical Properties:
1. Have properties of both metals and nonmetals.
Location:
Found along stairs (B, Si, Ge, As, Sb, Te, Po, At)
NOT Aluminum (Al)
Periodic Table
NOBLE GASES (INERT GASES)
Physical Properties:
1. Do not combine chemically with other
elements (does not form compounds).
2. All are gases at room temperature.
Location:
Last column – Group 18 (He, Ne, Ar, Kr,
Xe, Rn).
Spectrum Tube Demo
Periodic Table
HALOGENS
Physical Properties:
1.Vary greatly in color.
2.Solids, liquids, and gases.
Location:
Next to last column – Group 17 (F, Cl, Br, I).
They are very reactive and bond well
Periodic Table
STATES OF MATTER AT ROOM
TEMPERATURE
Liquids:
Gases:
Solids:
Periodic Table
Br, Hg (2)
H, He, N, O, F, Cl, Ar, Kr, Xe,
Rn, Ne (11)
All the rest of the elements
Radioactivity
Some elements will change (decay) into another
element.
Ex: Radon gas turns into lead.
These elements are called:
RADIOACTIVE
When these elements decay their nucleus
changes into another element and they give off
RADIATION.
3 Types of Radiation
1. Alpha Decay ( α ):
 Weakest –can be stopped by a piece of
paper.
2. Beta Decay ( β ):
 2nd strongest – can be stopped by
aluminum foil.
3. Gamma Rays ( γ ):
 Stopped by 5 cm of lead.
Each radioactive element has a certain
HALF – LIFE.
Half – Life:
The amount of time it takes for half of the
element to decay (change).
Example:
You have 8 m&m’s. If the half-life of m&m’s
is 1 minute, how many will be left after 3
minutes?
Number of m&m’s
8
4
2
1
Time
0
1
2
3
Example:
If you had 100g of a radioactive substance
that has a half-life of 4 days, how much
would be left after 8 days?
Radioactive substance
100g
50g
25g
Days
0
4
8
Example:
If you had 1000g of a radioactive substance
that has a half-life of 25 years, how much
would be left after 100 years?
Radioactive substance
1000g
500g
250g
125g
62.5g
Years
0
25
50
75
100