Transcript Atomic Structure and the Periodic Table Lesson 2

August 13, 2012
Mystery Elements! Use your periodic table
and the clues below to determine the identity
of 3 mystery elements:
1. This element, with a mass number of 207, is
poisonous.
2. This element, made of atoms with 78
electrons in the neutral state, is a very
expensive metal.
3. This element, made of atoms with 16
protons, is a gas that smells like rotten
eggs.
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Atomic Symbol: Pb
Atomic Number: 82
Mass Number: 207.2
207Pb
Atomic Symbol: Pt
Atomic Number: 78
Mass Number: 195.08
195Pt
Atomic Symbol: S
Atomic Number: 16
Mass Number: 32.07
32S
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I can compare and contrast ions and isotopes
of different elements.
I can use the mass number and atomic
number to calculate the number of neutrons.
I can research the properties of elements.
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Catalyst
Hour 1:
◦ Ions and Isotopes
◦ Atomic Structure Worksheet & Exit Slip
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Hour 2:
◦ Element Project
Sometimes, atoms of the same
element have different numbers of
neutrons. Atoms of the same
element with different numbers of
neutrons are called isotopes.
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Three isotopes of magnesium are
◦ Magnesium – 24 (24Mg)
◦ Magnesium – 25 (25Mg)
◦ Magnesium – 23 (23Mg)
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In your notes, write down the numbers of
protons, electrons, and neutrons for each of
the magnesium isotopes.
Discuss with your partner: what is the same
about these isotopes, what is different?
• Ions are atoms with a net charge. The ion is
charged because there are an unequal number of
protons and electrons.
• The charge is shown on the right side of the
symbol:
• Ex: Mg with 12 protons and 10 electrons Mg2+
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Positively charged ions have more protons
than electrons
◦ Ex: Ca2+ (calcium ion) has 20 protons and 18
electrons
 20 – 18 = 2
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Negatively charged ions have more electrons
than protons
◦ Ex: Br- (bromine ion) has 35 protons and 36
electrons
 35 – 36 = -1
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Sample:
◦ 19 protons, 20 neutrons, 18 electrons
 Answer: K+1
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+19 p + (-18 e) = +1
Now you try:
13 protons, 14 neutrons, 10 electrons
1 proton and no electrons
53 protons, 73 neutrons, 54 electrons
16 protons, 16 neutrons, 18 electrons
4 protons, 5 neutrons, 2 electrons
The atomic number always appears on the lower left side
of the symbol.
H
He
1
Li
2
3
Be
B
4
5
Mass numbers are written on the upper left side of the
symbol.
1
H
2
H
3
He
4
He
6
Li
7
Li
9
Be
10
B
11
B
The charge on an ion is shown on the right side of the symbol.
Cl-
Na+ Mg2+
Al3+ F-
O2-
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Catalyst
Hour 1:
◦ Ions and Isotopes
◦ Atomic Structure Worksheet & Exit Slip
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Hour 2:
◦ Element Project
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Three Part Project
Final Due Date: Wednesday August 22
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Purpose
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The purpose of this project is to allow you to
learn about one element on the Periodic Table.
You will research your element and then present
the information you find in a short report. Each
student will be assigned a different element. The
project contains three parts: (1) Element Card, (2)
Element Properties, and (3) History/Uses of the
Element essay.
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Part I: Element Card
You will get a piece of construction paper in
class. On this paper, make a periodic table
square for your element. The card must include
the name of your element, the atomic symbol,
atomic mass, and atomic number. Additionally,
you may decorate the card with drawings or
pictures that relate to your element. The atomic
symbol should be large. We will construct our
own periodic table with these cards.
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Part II: Element Properties
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One type of information you will find about your element
is the element’s various chemical and physical properties.
List the properties in a table on the back of your element
card.
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Required Properties: atomic number, average atomic mass,
ions the element forms (if any), isotopes and percent
abundance, state of matter in nature, color, and whether it
is a metal, non-metal, or semi-metal.
Optional Properties: boiling point, melting point, electron
configuration, texture, brittle/ductile, conductor of
electricity and/or heat, insulator; radioactivity; reactivity
with acids, bases, oxygen, metals; alkali metal, alkaline
earth metal, etc.; any other relevant properties.
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Part III: History / Uses of the Element
In this portion of the project, you will research man’s relationship to the
element. This portion of the project is a written report. Your report
must be at least one page typed. Here, you may include facts about the
discovery of the element.
What person/people discovered it? Where and when was it discovered?
In what country? Is there a story behind the identification or discovery
of the element?
You should also include information about how humans interact with the
element.
Where is the element found in nature? Is it found in ores or minerals? Is
it found in the sea or in the air? Do certain plants or animals have high
concentrations of this element? What processes must we perform to
acquire samples of the element? What is the element used for?
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“groups” are columns
“periods” are rows
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You will receive your element assignment.
Read and take notes on the portion of your
textbook about your element’s group.
Complete your Element Card.
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Edgardo A. -- Hydrogen
Jackeline A. -- Lithium
Jay A. -- Sodium
Eduardo A. -- Potassium
Yvette A. -- Beryllium
Paola A. -- Magnesium
Tania C. -- Boron
Susan C. – Aluminum
Melody C. -- Plutonium
Brandell C. -- Carbon
Anthony C. -- Silicon
Karen C. – Nitrogen
Luis V. -- Radium
•Saydy G. -- Phosphorous
•Rumaldo G. -- Arsenic
•Emeline L. -- Oxygen
•Kevin L. -- Sulfur
•Rudy M. -- Flourine
•Denise M. -- Chlorine
•Ana Q. -- Helium
•Zamir R. -- Neon
•Christian R. -- Argon
•Alejandra R. -- Gold
•Anthony S. -- Silver
•Jesus S. -- Iron
•Bernabe T. --Platinum
•Ivan Z. -- Mercury
•Nancy Z. -- Zinc
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Everyone: Read pp. 124 “The Main-Group
Elements”
Alkali Metals (Li, Na, K, Rb, Cs): pp. 125 & 128
“Most Elements are Metals”
Alkaline Earth Metals (Be, Mg, Ca, Sr, Ba, Ra): pp.
126 “The Alkaline Earth Metals” & 128 “Most
Elements are Metals”
Halogens (F, Cl, Br, I, At): pp. 126 – 127 “The
Halogens”
Noble Gases (He, Ne, Ar, Kr, Xe, Rn): pp. 127
“The Noble Gases”
Hydrogen (H): pp. 128
Transition Metals (Ti, Fe, Co, Ni, Cu, Zn, Pt, Au,
Hg, Ag, Sn, Pb): pp. 128 - 129
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http://www.rsc.org/periodic-table/
http://www.chemicalelements.com/index.ht
ml
http://www.webelements.com/pictures.html