IIIIII 1 The Periodic Table- Topic 5 Click for song Bellwork: Using your RB (pgs 78-83), define the...

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I II III1

The Periodic Table- Topic 5

Click for song

Bellwork: Using your RB (pgs 78-83), define the following words in your notebook: family, group, periodic law, period, metal, metalloid, nonmetal

Searching For an Organizing Principle

Chlorine, bromine, and iodine have very similar chemical properties.

2

Mendeleev’s Periodic Table (1869)

How did Mendeleev organize his periodic table? The Abbreviated History of the Periodic Table for

Regents Chemistry

6.1

3

Group Work

All members of the group should be participating ( 1 reader)

Use low voices and work cooperativelyI should hear CHEM Talk!!Lab should be completed by end of the

period.I will be watching and a group grade will

be assignedCooperation and diligence is

necessary….. 4

5

A. Dmitri Mendeleev (1869, Russian) Organized elements by

increasing ATOMIC MASS.

Elements with similar chemical properties were grouped together.

There were some discrepancies.

I. HISTORY

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B. Henry Moseley

ORGANIZED ELEMENTS BY INCREASING ATOMIC NUMBER.

Resolved discrepancies in Mendeleev’s arrangement.

The Periodic Law In the modern periodic table, elements are

arranged in order of increasing atomic number.

6.1

Mendeleev’s original table was according to mass. This was changed when Moseley discovered atomic number.

7

When elements are arranged in order of INCREASING ATOMIC #, elements with similar chemical properties appear at regular intervals.

The properties of the elements within a period change as you move across a period from left to right.

The pattern of properties within a period repeats as you move from one period to the next.

0

50

100

150

200

250

0 5 10 15 20Atomic Number

Ato

mic

Ra

diu

s (

pm

)

8

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1. Horizontal rowsCalled PERIODSAll elements in the same period have the same number of ENERGY LEVELS in their atomic structure

A. Arrangement of Table

II. ORGANIZATION OF THE ELEMENTS

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2. Vertical Columns

a) Called GROUPS OR FAMILIESb) All elements in the same group have the

same number of VALENCE ELECTRONS, therefore lose or gain the SAME number of electrons, form similar CHEMICAL FORMULAS and have similar CHEMICAL PROPERTIES

ex. XCl2 Group 2:

Be +2 Cl -1 = BeCl 2

Mg +2 Cl -1 = MgCl2

Remember: When

writing formulas,

use the criss-cross

rule to cancel out

oxidation states

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Elements can be classified by their properties and located on the Periodic Table as metals, nonmetals, metalloids or semimetals

Metals on the left

Nonmetals on the rightMetalloids or semimetals

III. Comparing Metals, Nonmetals & Metalloids

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III. Comparing Metals, Nonmetals & Metalloids

Elements on the Periodic Table are divided into three subgroups called METALS, NONMETALS and METALLOIDS

(semimetals).

Decrease metallic propertiesDecrease metallic properties

Increase Increase

metallic metallic

propertiesproperties

Increase Increase

nonmetallic nonmetallic

propertiesproperties

Click on

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METALS: located on the LEFT SIDE of the periodic table (except H); MORE THAN 2/3 of all elements

1. Chemical properties tend to LOSE ELECTRONS EASILY have LOW IONIZATION ENERGY (energy

needed to remove electrons) Metallic character INCREASES as

ionization energy decreases. have LOW ELECTRON AFFINITY

(attraction for electrons) form POSITIVE IONS when combining

with other atoms FRANCIUM most reactive

metal:SeeTableJ

14

2. Metals Physical Properties

good conductors of heat and electricity

LUSTROUS - reflect light, shine when they are polished

MALLEABLE - can be rolled or hammered into sheets

DUCTILE - can be drawn into wires

are SOLIDS at room temperature except for MERCURY (liquid)

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B. NONMETALS

1. Chemical properties tend to GAIN electrons to form

NEGATIVE IONS have high electron affinities

(electronegativity) produce COVALENT bonds by

SHARING electrons with other nonmetals

FLUORINE most reactive nonmetal: see Table J

located on the right side of

the periodic table (except for

Noble gases)

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2. Nonmetals Physical Properties exist as gases, molecular solids, or

network solids at room temperature except BROMINE (liquid)

BRITTLE - (shatters when struck) DULL - does not reflect light even when

polished POOR CONDUCTORS of heat and

electricity Allotropes: Different SHAPE & PROPERTIES forms from the

same element. Exist in two or more different forms. Therefore they have different crystalline structures and different physical and chemical properties

CARBON: coal; diamond, graphite OXYGEN: O2; O3 (OZONE)

Crystal Structure and Unit Cells

Carbon Allotropes

13.

3

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Buckminsterfullerene

The structure of a buckminsterfullerene is a truncated icosahedron made of 20 hexagons and 12 pentagons, with a carbon atom at the vertices of each polygon and a bond along each polygon edge. To become stable, the carbon atom needs 8 electrons in its outer shell, and covalently bonding with 3 other atoms will only make 7 electrons in its outer shell. This means that the one unbonded electron on every carbon atom is free to float around all of the compound's atoms. Electrons carry charge, so this free electron movement means that the buckminsterfullerene can conduct electricity very well. This, because of its size, makes it very useful in nanotechnology.

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C. METALLOIDS (semi-metals)

Found lying on the jagged line between metals and nonmetals flatly touching the line (except Al and Po).

B,Si,Ge,As, Sb, & Te Exhibit properties of both

metals and nonmetals Behave as nonmetals but

their conductivity is like metals

SEMICONDUCTORS – Si and Ge

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Squares in the Periodic Table

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Many properties of the elements change

in a predictable way as you move

through the periodic table – these

systematic trends are called periodic

trends..(use reference Table S for data comparison)

Periodic Trends

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Reference Table S

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© 1998 LOGAL

1. Atomic Radius

DESCRIPTION: ½ THE

DISTANCE BETWEEN 2

ADJACENT NUCLEI

Trends in Atomic Size

The atomic radius is one half of the distance between the nuclei of two atoms of the same element when the atoms are joined.

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TREND GOING ACROSS A PERIOD

What is the ‘trend’ as you move left to right? ATOMIC

RADIUS DECREASES

Explanation: ---THE GREATER THE #PROTONS (NUCLEAR

CHARGE), THE STRONGER THE PULL ON THE E’S BRINGING

THEM CLOSER INTO THE NUCLEUS THEREFORE ATOMIC

RADII DECREASES

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TREND GOING DOWN A GROUP OR FAMILY

What is the ‘trend’ as you move down a group? ATOMIC RADIUS INCREASES

Explanation: ----AS EACH ELEMENT GOES DOWN A GROUP,

YOU ADD ANOTHER NRG LEVEL INCREASING THE SHIELDING

(KERNEL E- BLOCK THE ATTRACTION BETWEEN THE

NUCLEUS AND THE VALENCE E-)

Ions

Positive and negative ions form when electrons are transferred between atoms.

6.3

11p+

12 n

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Ions

Positive and negative ions form when electrons are transferred between atoms.

6.3

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Trends in Ionic Size

Relative Sizes of Some Atoms and Ions

29

30

IONIC RADIUS

Description: A LOSS OR GAIN IN ELECTRONS BY AN ATOM WILL CHANGE THE SIZE OF

THE RESULTING ION

Ionic Radii

Metals Nonmetals

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COMPARISON OF METALS TO NONMETALS

If you generally compare ionic size for metals and nonmetals, metal ionic sizes are SMALLER and nonmetal ionic sizes are BIGGER.

This is because metals tend to LOSE electrons and form CATIONS (and get smaller) while nonmetals tend to GAIN electrons and form ANIONS (and get larger).

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METALS: TREND GOING ACROSS A PERIOD Trend: As you move left to right for METALS, ionic size

DECREASES

Explanation: METALS LOSE ELECTRONS FROM THEIR OUTERMOST SHELL

METALS: TREND GOING DOWN A GROUP Trend: As you move down a group for METALS, ionic size

INCREASES

Explanation: AS YOU MOVE DOWN A GROUP, YOU ADD ANOTHER ENERGY LEVEL THEREBY INCREASING THE SIZE DUE TO THE INCREASED # OF ELECTRONS

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NONMETALS: TREND GOING ACROSS A PERIOD Trend: As you move left to

right for NONMETALS, ionic size decreases.

Explanation: NONMETALS GAIN ELECTRONS WHICH ARE ATTRACTED TO THE PROTONS IN THE NUCLEUS

NONMETALS: TREND GOING DOWN A GROUP

Trend: As you move down a group for NONMETALS, ionic size INCREASES.

Explanation: AS YOU MOVE DOWN A GROUP, YOU ADD ANOTHER ENERGY LEVEL THEREBY INCREASING THE SIZE DUE TO THE INCREASED # OF ELECTRONS

© 2002 Prentice-Hall, Inc.

34

IONIZATION ENERGY (IE)

Description: AMOUNT OF ENERGY NEEDED TO REMOVE AN E- FROM AN ATOM. Atoms with a HIGH ionization energy

hold onto electrons MORE EASILY and are less likely to give them up.

Atoms with a LOW Ionization Energy hold onto electrons LOOSELY and are more likely to LOSE electrons

Ionization Energy

Energy needed to remove the most loosely bound electron from a neutral gaseous atom

X + energy X+ + e-

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Trends in Ionization Energy

36

Trends in Ionization Energy

37

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TREND GOING ACROSS A PERIOD

What is the ‘trend’ as you move left to right? IE INCREASES Explanation: AS THE #PROTONS (AKA: NUCLEAR CHARGE)

INCREASES, THERE IS A GREATER PULL ON THE E’S REQUIRING MORE NRG TO REMOVE THEM

TREND GOING DOWN A GROUP OR FAMILY

What is the ‘trend’ as you move top to bottom? IE DECREASES

Explanation: Atom size increases making the outermost electron farther away from the nucleus therefore making it easier to remove

Shielding increases

1

2

3

4 5

6

7

INCREASES

DECREASES

Trends in Ionization Energy

39

40

ELECTRONEGATIVITY (EN) Description: MEASURE OF AN ATOM’S ABILITY TO ATTRACT

ELECTRONS

Atoms with a HIGH Electronegativity have a STRONGER attraction for bonded electrons

Atoms with a LOW Electronegativity have a WEAKER attraction for bonded electrons

Based on a scale of 4, Fluorine has the greatest EN

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TREND ACROSS A PERIODWhat is the ‘trend’ as you move left to right? EN INCREASESExplanation: THERE ARE MORE PROTONS

(INCREASED ATOMIC NUMBER) WHICH

INCREASES THE ELECTRONS ATTRACTION

TREND GOING DOWN A GROUP OR FAMILY

What is the ‘trend’ as you move top to

bottom?

EN DECREASES

Explanation: AS YOU GO DOWN A GROUP

THERE ARE MORE ELECTRONS AND MORE NRG

LEVELS SO THE ATTRACTION GETS WEAKER

42

Periodic Trends Summary(use reference Table S for data comparison)

TrendAcross a Across a period period

Down a Down a groupgroup

Ionization energy

increasesincreases decreasesdecreases

Electronegativity

increasesincreases decreasesdecreases

Atomic radii decreasesdecreases increasesincreases

Metallic properties

decreasesdecreases increasesincreases

Click on for video clip

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IV. Classification

Alkali MetalsAlkaline Earth MetalsTransition MetalsHalogensNoble Gases

Click for

song

44

Group 1: Alkali Metals

extremely reactive (not found free in nature)

form stable ionic compoundsreact with water to form a basereact with air to form oxidesreact with acids to form salts

Click on for video clip (2:56 min)

45

Group 2: Alkaline Earth Metals

reactive (not found free in nature) - form stable ionic compounds

react with water to form a basereact with air to form oxides react with acids to form salts

Click on for video clip

46

Groups 3-11: Transition Metals

multiple positive oxidation statesLose electrons from two outermost

energy levelsIons form colored solutions

Ex. CuSO4 (due to the Cu 2+ ion)

47

Group 15 – unique features

Members range from typical nonmetals (nitrogen and phosphorus) through metalloids (arsenic and antimony) to metals (bismuth)

NitrogenForms stable diatomic molecules with a triple

bondComponent of proteinForms some unstable compounds that are used as

explosives

PhosphorusComponent of nucleic acids (DNA, RNA)More reactive than nitrogen at room temperature

48

Group 16 – unique Features

Members range from typical nonmetals (oxygen and sulfur) through metalloids (selenium and tellurium) to metals (polonium)

Solids except oxygen Oxygen can exist as O2 and O3 (it is an allotrope)

Polonium is radioactive

49

Group 17: Halogens

very reactive nonmetals - high electronegativity

not found free in natureform diatomic molecules when

freereact with metals to form salts

(halides)Found in all three phases (s, l,

g) due to differences in Van der Waals forces (these are weak)

50

Group 18: Noble Gases

Have complete outer shellsAlmost inert (not reactive);

stableKrypton, xenon, and radon

form compounds with oxygen and fluorine

Referred to as monatomic gases

51

TODAY……..TODAY……..

1. Using a pencil, transfer your RB answers to your scantron form –

In the green box, write “RB Topic 5 #1-45”.

Turn in BOTH the scantron and your written work.

52

2. Assemble into NEW groups according to the number on your card from yesterday (refer to your sheet). Take your notes and 5 questions with you. Using your notes, discuss & complete the Teachback WS questions pertaining to your group.

Use the post-it notes for any questions you may have THAT MAY NEED ANSWERING

Folks who did the Noble gases will need to meet briefly for a few moments.

53

3. Return BACK to your original groups and BEGIN your teachback. This NOT a silent lesson – use your “6 inch” voices to teach the other members. Ask your questions to ascertain clarity. At the end of this session, everyone in the group should have the Teachback WS completed.

Use the post-it notes for any questions you may have THAT NEED ANSWERING..

Once finished, begin RB questions 46-90.

Cooperation and diligence is necessary….. I will be watching and listening.

54

TEACHBACK PROJECT REVIEW

Alkali MetalsAlkaline Earth MetalsTransition MetalsHalogensNoble Gases

Click for

song

55

GROUP 1

1. The name of this group is ALKALI METALS

2. Does this group contain metals or nonmetals? METALS

3. Alkali metals (lose or gain)l LOSE electrons becoming (positive or negative) ions? POSITIVE

4. Describe the reactivity of the elements in this group as the atomic number increases. INCREASES

5. Are they (more or less) MORE reactive than all of the elements in Group 2 and why? THEY HAVE LOW IONIZATION ENERGIES

video

56

Group 1 continued:

6. Can these compounds be found in nature in the elemental or combined state? COMBINED STATE IN THE FORM OF A SALT

7. What type of compounds do they normally form (ionic or covalent)? IONIC (M + NM)

8. If element Y represents an alkali metal, what is it’s general formula for the reaction with a:

Chloride: YCl Oxide: Y2O

9. What is the most reactive metal in this group? FRANCIUM

57

GROUP 21. The name of this group is ALKALINE

EARTH METALS.

2. Does this group contain metals or nonmetals? METALS

3. They (lose or gain) LOSE electrons & form (positive or negative) ions POSITIVE ?

4. Describe the reactivity of the elements in this group as the atomic number increases (increases or decreases) INCREASES

5. Are they (more or less) LESS reactive than all of the elements in Group 1 and why? THEY HAVE GREATER IE

video

58

Group 2 continued:6. Can these compounds be found in

nature in the elemental or combined state? COMBINED STATE IN THE FORM OF A SALT

7. What type of compounds do they normally form (ionic or covalent)? IONIC (M + NM)

8. If element Z represents an alkaline earth metal, what is it’s general formula for the reaction with a:

Chloride ZCl2 Oxide: ZO

59

GROUP 151. What is this group referred to as? NITROGEN GROUP

2. Name the diatomic element in this group? NITROGEN

3. Classify each element in this group as a metal, non-metal or semi-metal (metalloid).

metals: ANTIMONY, BISMUTH nonmetals: NITROGEN, PHOSPHORUS semi-metal: ARSENIC

4. Explain what happens to the reactivity of a non-metal as the atomic number increases. DECREASES .

5. Which is the most reactive non-metal in this group? PHOSPHORUS

6. Is nitrogen a (diatomic or monatomic) DIATOMIC molecule & what type of bond is found in nitrogen? TRIPLE COVALENT

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GROUP 161. Classify each element in this group as a metal, non-metal

or semi-metal.metals: POLONIUM nonmetals: OXYGEN, SULFUR, SELENIUM semi-metal: TELLERIUM

2. Name the diatomic element in this group. OXYGEN

3. Define an allotrope? DIFFERENT FORMS OF AN ELEMENT IN THE SAME PHASE WITH HAVING DIFF CHEM & PHYSICAL PROPERTIES

4. Which element(s) in this group is an allotrope? SULFUR, OXYGEN (O2 and O3)

5. What type of element is Polonium? RADIOCATIVE METAL How can you tell it is radioactive? IT’S ATOMIC NUMBER IS GREATER THAN 83

61

TRANSITION ELEMENTS (groups 3B-

12)

1.1. Which element is a liquid at room temperature? Which element is a liquid at room temperature? MERCURY (Hg)

2. What are the four main characteristic chemical 2. What are the four main characteristic chemical properties of transition elements? properties of transition elements?

MULTIPLE POSITIVE OXIDATION STATES IONS FORM COLORED SOLUTIONS LOSE ELECTRONS FROM TWO

OUTERMOST ENERGY LEVELS UNFILLED D ORBITALS

62

GROUP 17

1. The name of this group is HALOGENS

2. Name and classify the elements in this group: METALS: At NONMETALS F, Cl, Br, I

3. Halogens (lose or gain) GAIN electrons becoming (positive or negative) ions? NEGATIVE

4. Why is astatine not included much in these discussions? NOT ENOUGH AVAILABLE TO STUDY

5. What would the general formula of a Group 17 element (represented by X) combined with magnesium of

group 2? MgX2

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6. What is the most reactive element in this group? FLUORINE

7. Can these compounds be found in nature in the elemental or combined state? COMBINED STATE AS SALTS

8. What type of salts do these elements form? HALIDES

9. For each state of matter, list the element(s) in this group. solid: IODINE liquid: BROMINE gas: CHLORINE, FLUORINE

10. What type of forces of attractions account for the different states of matter that exist and the high MP’s and BP’s as you go down the group? VAN DER WAALS FORCES (weak forces that get stronger as you go down the group )

64

GROUP 18The name of this group is called NOBLE GASES.

What type of molecules do these gases form? (monatomic or diatomic) MONATOMIC

Describe the electron arrangement in the outermost energy level of all these elements. STABLE OCTECT – INERT GAS STRUCTURE

Which element has only two electrons? HELIUM

Describe the reactivity of the elements in this group. THEY ARE UNREACTIVE (Kr and Xe can be forced to react with F in lab settings)

65

Topic 5 RB ANSWERS #43-90

71) _1_72) _3_73) _1_74) _2_

56) _2__

57) _3__

58) _3__

59) _2_

60) _1__

46) _2_

47) _1_

48) _4_

49) _1_

50) _1_51)_ 2_

52) _4_

53)_4_

54) _3_

55) _2_

61) _3_

62) _3_

63) _1_

64) _1_

65) _3_

66) _1_

67) _2_

68) _2_

69) _4_

70) _1_

43) 4

44) 2

45) 1

66

79) They both follow the octet rule (8 valence e’s)

81) Hydrogen is a NM & doesn't have the characteristics of other group 1 members other than one valence e

82) LARGEST: aluminum SMALLEST: carbon HIGHEST IE: carbon LOWEST IE: aluminum

83) Same number of valence e’s

84) Metals have fewer valence e’s. As you move to the right of the PT, there are more val e’s. Once the orbitals are full, a noble gas configuration is met (8 val e’s)

85) Metals become positive ions

87) MCl2 88) MgX2 89) X2O

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