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Chapter 6THE PERIODIC TABLE
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Introduction Activity
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Label the GROUPS & PERIODS(on BOTH sides)
1 18
1 2 13 14 15 16 17
2
3 3 4 5 6 7 8 9 10 11 12
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5
6
7
6
7
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Make Yourself a KEY!
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Metals
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Transition Metals
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Metalloids
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Non Metals
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Make Yourself a KEY!
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Representative Elements1 18
1 2 13 14 15 16 17
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3 3 4 5 6 7 8 9 10 11 12
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5
6
7
6
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Make Yourself a KEY!
Hydrogen
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Alkali Metals
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Alkaline-Earth Metals
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Boron Group
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Carbon Group
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Nitrogen Group
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Oxygen Group
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Halogens
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Noble Gases
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Lanthanides
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Actinides
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All Together!
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Make Yourself a KEY!
Chapter 6 Vocabulary1.Alkali metals
2.Alkaline earth metals
3.Anion
4.Atomic radius
5.Cation
6.Electronegativity
7.Halogens
8.Inner transition metal
9.Ion
10. Ionization energy
11. Metalloids
12. Metals
13. Noble gases
14. Nonmetals
15. Periodic law
16. Representative elements
17. Transition metal
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Review from yesterday! Complete the chart:
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Element Symbol Group Number
Period Number
Group Name Metal, Nonmetal, or
Metalloid?
Nitrogen N 15 2 Nitrogen Group Nonmetal
Platinum
Sn
15 5
Potassium
17 4
Tin
Sb
K
Br
1014
1
6
5
4
Transition Metals
Metal
Carbon Group
MetalNitrogen Group
Alkali Metals
Halogens
Metalloid
Metal
Nonmetal
Pt
Antimony
Bromine
Section 6.1 NotesOrganizing the Elements READ PAGES 155-160
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How did chemists begin to organize the known elements?
Chemists used the properties of elements to sort them into GROUPS.
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1700 13 elements were identified
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Included:-Copper-Silver-Gold-Carbon
1765-1775 5 new elements were identified
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Included:-Hydrogen-Nitrogen-Oxygen
1829 J.W. Döbereiner (Johann Wolfgang)
◦ German chemist◦ Grouped some elements into triads
◦ Set of three elements with similar properties
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Cl, Br, I have very similar chemical properties.
Can you find them on the Periodic Table?Can you find them on the Periodic Table?
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1869 Dmitri Mendeleev◦Russian chemist◦Published the first table of elements◦Arranged the elements in order of increasing atomic mass
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Mendeleev was amazing because he• left spaces in his table for elements not yet discovered• predicted properties for these undiscovered elements correctly
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Mendeleev’s 1st Periodic Table
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In this early version of Mendeleev’s periodic table, the rows contain elements with similar properties.
What was wrong with Mendeleev’s Periodic Table?
Let’s look at your Periodic Table What did Mendeleev’s Periodic Table go by?
◦ Atomic Mass
Any discrepancies? What does yours go by?
◦ Atomic Number
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1913
Henry Moseley◦British physicist◦Determined the atomic number for elements
◦Arranged the elements in order of increasing atomic number◦ Today’s Periodic Table
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Today’s Periodic Table
Periodic Law when elements are arranged by increasing atomic number, properties of the elements tend to repeat
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Metals• to the left of the stair-step line
• most of the elements (80%)
• Properties◦ Good conductors of heat and electricity◦ Shiny (luster)◦ Solid at room temperature
◦ Except liquid mercury◦ Ductile
◦ Drawn into wires like copper wire◦ Malleable
◦ Hammer into thin sheets like aluminum foil
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Metals
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Of all the elements that make up the world in which we live – solids, liquids,
gases – most are metals.• There are metals such as
aluminum, zinc, gold, copper, tin, and nickel – and ones you might not think of as metals, such as calcium, which is present in bones and teeth. Did you know that the average human body contains more than 2 lbs of calcium?
AlZnA
uCu
Sn
Ni
Ca
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Some metals are dangerous.
• Potassium reacts violently with water creating hydrogen gas. Cesium and rubidium will explode if they touch water.
K
CsRb
https://www.youtube.com/watch?v=uixxJtJPVXk
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Mercury is poisonous.• In fact, the phrase
“mad as a hatter” arose because in past centuries, fumes from the mercury used in the hat making process affected the mental health of workers in that industry!
• Platinum, Pt, is one of the rarest and most valuable of all metals. It is used to make jewelry and used extensively in industry.
• The high density of osmium, Os, – a metal in the same period as platinum – means that a brick of the metal can weigh as much as a small car. Osmium is used in fountain pen nibs and surgical needles.
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Can you find element names hidden in these sentences?
1. Nick, elbows off the table please!2. Grandpa is looking older.3. Your feet are a little stinky.4. Do you care about the environment?5. I placed a simple ad in the paper.
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Nonmetals to the right of the stair-step line most are gases, few solids
◦except liquid bromine
Properties:◦poor conductors of heat and electricity◦solids tend to be brittle
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Nonmetals
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Diatomic Elements
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BrINCl HOF
LABEL THEM ON YOUR P.T.
Metalloids Touch the stair-step line
◦ Except aluminum and polonium
Have properties of both metals and nonmetals
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Si
Metalloids
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Metals / Metalloids / NonmetalsJust like Intro Activity
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Metals, Nonmetals, and Metalloids
Inferring: What is the purpose for the black stair-step line?
Quick QuizSECTION 6.1
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1. The modern periodic table has elements arranged in order of
a. colors.b. melting and boiling points.c. increasing atomic mass.d. increasing atomic number.
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2. Mendeleev arranged the elements in his periodic table in order of increasing
a. atomic mass.b. number of protons.c. number of electrons.d. atomic number.
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3. Which one of the following is NOT a general property of metals?
a. ductilityb. malleabilityc. having a high lusterd. poor conductor of heat and
electricity
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What’s Next?
Book Work: ◦Page 160 #’s 1-7
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Page 160 #1-71. How did chemists begin the process of organizing elements?2. What property did Mendeleev use to organize his periodic
table?3. How are elements arranged in the modern periodic table?4. Name the three broad classes of elements.5. Which of the sets of elements have similar physical and
chemical properties?a. Oxygen, nitrogen, carbon, boronb. Strontium, magnesium, calcium, berylliumc. Nitrogen, neon, nickel, niobium
6. Identify each element as a metal, metalloid, or non-metal.a. Goldb. Siliconc. Sulfurd. Barium
7. Name two elements that have properties similar to those of the element sodium. 58
1. How did chemists begin the process of organizing elements?
Chemists used the properties of elements to sort them into
groups, or triads.
2. What property did Mendeleev use to organize his periodic table?
Increasing atomic mass
3. How are elements arranged in the modern periodic table?
Increasing atomic number
4. Name the three broad classes of elements.
Metals, Non-Metals, and Metalloids
5. Which of the sets of elements have similar physical and chemical properties?
(B)strontium, magnesium,
calcium, beryllium
6. Identify each element as a metal, metalloid, or non-metal.
A) Metal (Au)B) Metalloid (Si)C) Non Metal (S)
D) Metal (Ba)
7. Name two elements that have properties similar to those of the element sodium.
Li, K, Rb, Cs, Fr
Section 6.2 NotesClassifying the Elements READ PAGES 161-167
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Representative Elements Groups 1A through 8A◦Groups 1, 2, 13-18
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Representative Elements
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Transition Elements Transition metals◦Group B
◦ Groups 3-12
Inner transition metals◦Last 2 rows on the periodic table
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Transition ElementsInner Transition Elements
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Similar to your colored Periodic Table
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The periodic table displays the symbols and names of the elements, along with information about the structure of their atoms.
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Periodic Table Key
Quick QuizSECTION 6.2
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1. Which one of the following is incorrectly labeled?
a. Ne, noble gasb. Cu, transition metalc. Ga, transition metald. Cl, halogen
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What’s Next? Book Work: ◦Page 167 #’s 10, 12, 14
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10. What information can be included in a periodic table?
Symbols and names.Structure. Properties.
12. Why do the elements potassium and sodium have similar chemical properties?
K and Na are in the same group.
(Alkali Metals)
14. Which of the following elements are transition metals?
Cu, Sr, Cd, Au, Al, Ge, Co
Section 6.3 NotesPeriodic Trends READ PAGES 170-178
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What does the word periodic mean to you? Periodic
◦Happens in intervals
What are some examples of things that happen periodically?◦Birthdays, holidays, periodicals
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Why is the periodic table called “The Periodic Table”? the properties of elements repeat
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Trend
◦A predictable change
Periodic Trend
◦ Properties of the elements repeat and form patterns
◦ Allows us to make predictions about the chemical behavior of elements◦ How elements will react with other
elements◦ Many trends exist in the
periodic table
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Atomic Radius Half the distance between two nuclei of the same atom Describes the size of the atom
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Atomic Radius Trend
DOWN A GROUP Increases Why?
◦ Number of energy levels increases
◦ Period 1 = 1 e. l., ◦ Period 2 = 2 e. l., ◦ Etc…
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H
Li
Na
K
Rb85
Atomic Radius Trend
ACROSS A PERIOD Decreases Why?
◦ Electron / proton attraction increases◦ Opposite of tug of war!
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Na Mg Al Si P S Cl Ar
Trends in Atomic Size
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Predicting: If a halogen and an alkali metal are in the same period, which one will have the larger radius? alkali metal
Shielding Effect “shielding” is the nuclear pull on electrons Valence electrons are “shielded” from the pull / charge of the nucleus by all the electrons in between.
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Ions An atom with a charge
Cation◦ Positively charged ion◦ Formed by metals◦ Lost electrons
Anion ◦ Negatively charged ion◦ Formed by nonmetals◦ Gained electrons
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How do ions form?
Positive and negative ions form when electrons are transferred between
atoms.
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Positive Ions
When a sodium atom loses an electron, it becomes a positively charged ion.
Interpreting Diagrams: What happens to the protons and neutrons during these changes?
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Negative Ions
When a chlorine atom gains an electron, it becomes a negatively charged ion.
Interpreting Diagrams: What happens to the protons and neutrons during these changes?
CationMetals
AnionNonmeta
ls
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This diagram compares the relative sizes of atoms and ions for selected alkali metals and halogens. The data are given in picometers.
Comparing and Contrasting:◦ What happens to the radius when an atom forms a cation?◦ When an atom forms an anion?
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Ionic Size Size of the ion compared to the parent atom Cations
◦ Positive ions are smaller than the atom it comes from◦ Why?
◦ It lost electrons
Anions◦ Negative ions are larger than the atom it comes from
◦ Why?◦ It gained electrons
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Trends in Ionic Size
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Ion
ic R
ad
ius
Incr
ease
s
Ionic Radius Decreases
First Ionization Energy energy needed to remove an electron from an atom
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First Ionization Energy Trend
DOWN A GROUP Decreases Why?
◦ Valence electrons are farther away from the nucleus
ACROSS A PERIOD Increases Why?
◦ The atom becomes more stable with more valence electrons
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What would the 2nd Ionization Energy mean?
Energy needed to
remove the second electronWhat would the 3rd
Ionization Energy mean?
Energy needed to
remove the third electron
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Why are elements such as H and He missing some ionization energy values?
Multiple Ionization Energies
Trends in Ionization Energy
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Predicting: Which element would have the larger first ionization energy, an alkali metal in period 2 or an alkali metal in period 4?Period 2 alkali metal
Electronegativity The ability of an atom to attract electrons to itself when bonded to another atom
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Electronegativity Trend
DOWN A GROUP Decreases Why?
◦ Valence electrons are farther away from the nucleus
◦ Same reason as ionization energy
ACROSS A PERIOD Increases Why?
◦ Atom becomes more stable with more valence electrons
◦ Same reason as ionization energy
◦ Don’t count noble gases
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Most Active Elements Most active metal
◦ Fr (Francium)
Why?◦ Lowest
electronegativity
Most active nonmetal ◦ F (Fluorine)
Why? ◦ Highest electronegativity
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Summary of TrendsRECAP
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Atomic Size
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Decreases
Incr
ease
s
Increases
Decr
ease
s
Ionization energy
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Increases
Decr
ease
s
Electronegativity
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Page 178: Draw arrows to show periodic trends below.
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Quick QuizSECTION 6.3
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1. Which of the following sequences is correct for atomic size?
a. Mg > Al > Sb. Li > Na > Kc. F > N > Bd. F > Cl > Br
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2. Metals tend to
a. gain electrons to form cations.b. gain electrons to form anions.c. lose electrons to form anions.d. lose electrons to form cations.
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3. Which of the following is the most electronegative element?
a. Clb. Sec. Nad. I
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What’s Next? Book Work: ◦Page 178 #’s 16-23
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16. How does atomic size change within groups and across periods?
In general, atomic size increases from top to bottom
within a group and decreases from left to right
across a period.
17. When do ions form?
Positive and negative ions form when electrons are
transferred between atoms.
18. What happens to first ionization energy within groups and across periods?
First ionization energy tends to decrease from top to
bottom within a group and increase from left to right
across a period.
19. Compare the size of ions to the size of atoms from which they form.
Cations (+) are always smaller than the atoms from which they
form.Anions (-) are always larger than
the atoms from which they form.
20. How does electronegativity vary within groups and across periods?
In general, electronegativity values decrease from top to bottom within a group. For
representative elements, the values tend to increase from left to right across a period.
21. In general, how can the periodic trends displayed by the elements be explained?
The trends that exist among these properties can be
explained by variations in atomic structure.
22. Arrange the elements in order of decreasing atomic size: Sulfur, Chlorine, Aluminum, Sodium.
Sodium > Aluminum > Sulfur > Chlorine
23. Which element in each pair has the larger first ionization energy?
a) Sodium, Potassiumb) Magnesium, Phosphorus
You need to know the NAME (Spelling Counts)NAME (Spelling Counts) and
SYMBOLSYMBOL of the following elements (not the location)
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Ti Cr Mn Fe Co Ni Cu Zn As Br
Rb Ag Sn I
Ba Pt Au Hg Pb
Fr
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The Periodic LawA PUZZLE ACTIVITY
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Introduction The present organization of the elements is a product of the first periodic table published by Dmitri Mendeleev in 1869. The amazing accuracy of his predictions has been very important to chemists in this century. However, the basis of his arrangement was the atomic masses of the elements. This approach proved incorrect as it would have placed some elements in a group with dissimilar properties. Henry Moseley rearranged the table on the basis of the atomic numbers of the elements. In accordance with Moseley’s revision, the periodic law states: the properties of the elements are periodic functions of their atomic numbers.
Each of the 100+ known elements has its own set of characteristic properties. These range from solid to gas, lustrous to dull, low to high melting points, various colors, and so on. The elements are arranged within the periodic table into groups (vertical columns) and periods (horizontal rows). This arrangement reflects the periodic or repeating nature of the properties of the elements.
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Purpose In this activity, you will use your knowledge of periodic properties and a list of clues to correctly arrange the elements from a scrambled periodic table.
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Procedure / Clues The following sets of elements belong together in groups:
◦ PSIF, JXBE, ZRD, LHT, QKA, WOV, GUN, YMC
Letter clues:
The electrons of atom N are distributed over three energy levels.
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J has an atomic number three times that of TU has a total of six electronsI2A is the simple formula of an oxideP is less dense than SS is an alkali metalE is a noble gasW is a liquidZ has the smallest atomic mass in its groupB has ten protonsO has an atomic number larger than VD has the largest atomic mass of its group
C has five electrons its outer energy levelF is a gasX has an atomic number one higher than FL is an alkaline earth element with atomic mass of 40Y is a metalloidO is a halogenThe atomic mass of T is more than that of HQ has an atomic mass 2 times AAtoms of I are larger than those of SM has an atomic number one less than that of AThe atomic radius of K is the largest of the group
Place the correct letter below in their appropriate spot according to the Periodic Table!
1 2 13 14 15 16 17 18
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Let’s do one together…J has an atomic number three times that of TU has a total of six electrons
Then you know that GUN are in this group
Have FunEXTRA CREDIT – DUE TOMORROW
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Answers
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1 2 13 14 15 16 17 18
F X
P H Z U M A V B
S T R N C Q O E
I L D G Y K W J
