Name:________________________________ Period:___ Date:________ Points:____/100

Chapter-6: The Periodic Table of Elements

TOPICS:6:1 History of the Periodic table

Mendeleev’s Periodic table and its problems

6:2 Modern Periodic table1. Structure of the Periodic table:

a. Periodic lawb. Periods and Groupsc. Three broad classes of elements and their locations on the periodic table

2. Properties of the 3 classes of elements a. Metalb. Nonmetalsc. Metalloids

3. Sorting elements based on chemical propertiesa. Alkali metals b. Alkaline earth metalsc. Halogensd. Noble gasese. Representative elementsf. Transition elements g. Inner-transition metals

4. Sorting elements based on electron configuration (4-types)a. s-blockb. p-blockc. d-blockd. f-block

5. Periodic trends:a) Atomic sizeb) Ionization energyc) Ionic sized) Electronegativity

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6:1 History of the Periodic table

The way elements are arranged in the MODERN periodic table explain many chemical and physical properties of elements. For thousands of years, the only known elements were:__________, ___________ and ____________. During the mid 1800’s, many chemists tried to organize the known elements in table-format. During this time, very little was known about atomic structure.

Mendeleev’s Periodic table and its problems

The most famous of these is the Russian chemist, Dimitri Mendeleev’s table. In _______ he arranged elements into rows called “periods” and columns called “groups.” Element s with similar ______________ (properties) were placed in groups and organized in the order of increasing atomic mass. Due to the predictive-properties of his periodic table, Mendeleev was able to predict the chemical properties of elements that had not been discovered yet. He left blank spaces for such elements. When these elements were discovered later,

they had properties described by Mendeleev – this caused him and his periodic table to gain much international recognition.

The major issue with his table was that he arranged elements based on their __________ ________. Recall that isotopes have very similar chemical properties. According to Mendeleev, isotopes of a given element will be placed in different groups due the differing __________.

Question: How can you overcome this issue? (CLUE: what makes one element different from another- Protons, neutrons or electron numbers?)_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

6:2 Modern Periodic table1. Structure of the MODERN Periodic table: a. Periodic law:_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Group numbering systems (group-A vs. Group-B and group 1-18)

Group A elements: have valence shell electrons filling in ____ (1A and 2A) and ____ (3A to 8 A) orbitalsGroup B elements: have valence shell electrons filling in ____ (1B and 8B) orbitals

c. Three broad classes of elements and their locations on the periodic table: * Color your periodic table showing each different class.

Metals: _______________________________________________________________________________ Non-metals: ___________________________________________________________________________ Metalloids:_____________________________________________________________________________

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KEY POINTS OF THE ARRANGEMENT OF ELEMENTS IN THE MODERN PERIODIC TABLE:

1. Atoms of elements arranged in order of increasing ________ _________ (protons)

2. There are______ periods represented by ROWS and _____ groups represented by COLUMNS

3. Each period represents a Principle Energy Level or __________ (n=1 to n=7)

4. There are more elements in ________ numbered periods because there are more orbitals in those energy levels

5. Elements within a group have similar chemical and physical ____________

6. Properties of elements in a period change as you go from left to right but the properties within a period ____________ as you move from one to another period

7. Three broad classes of elements: majority of the elements are metals (left side), some are nonmetals (upper right) and in between these are a few metalloids

8. ___________ a period elements become less metallic

2. Properties of the 3 classes of elements

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3. Sorting elements based on chemical properties:a. Alkali metals b. Alkaline earth metalsc. Halogensd. Noble gases

e. Representative elementsf. Transition elements g. Inner-transition metals

Name:________________________________ Period:___ Date: 11-28-2018

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Definitions:

Ductile =

Malleable =

Electronegative =

Electropositive =

Cations Anions

Sorting elements based on chemical properties:

a. Alkali metals b. Alkaline earth metals

c. Halogens d. Noble gases5

d. Representative elements:

e. Transition elements:

f. Inner transition elements:

4. Sorting elements based on electron configuration (4-types)a. s-block =

b. p-block=

c. d-block=

d. f-block=

Name:________________________ Period:____ Ch: 6 Periodic table notes contd. 12-11-2018

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Elements are arranged in increasing atomic number but there are more trends in the periodic table. These are summarized below:

Key points on the arrangement of elements in the periodic table based on groups and electron configuration:

1.Determining the number of Valence electrons:

Write the number of valence electrons above each group:

2.Determining the Oxidation number of elements based on their location on the Periodic table Oxidation number = the number of valance electrons taken or given away by an atom/element to obtain a noble gas electron configuration. (Ex: Na has an oxidation number of +1 as it loses its valence electron to obtain the electron configuration of Ne which is more stable.)

Fill out the missing oxidation numbers in the figure below:

What are the oxidation numbers of the elements below:

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Li and Na ______Mg and Ca _____B, Al and Ga _____

C, Si and Ge _____N, P and As _____O, S and Se ______

F, Cl, Br, I ______ He, Ne, Ar, Kr______

3. How to find valence shell Electron configuration: In elements with S and P block electrons, their Valance shell numbers are the period number in which they are located. The valence electron numbers are the Group-A number in wish they are located. Ex: F is in group 7A and Period 2. So its valence shell is 3 and it has 7 valence electrons. And these 7 electrons are found in S and p orbitals. 2 electrons in 2s and the remaining electrons in 2P. so the final VALANCE electron configuration is: 2s2 2p5.Fill out the valence electron configurations in the periodic table below:

4. Drawing Lewis dot-Structures of valence electrons:

Name:________________________ Period:____ Ch: 6 Periodic table notes contd. 12-12-2018

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PERIODIC TRENDS

DEFINITIONS:Cation (+ ion) = an atom that has _______one or more electrons (has more protons than electrons)Anion (- ion) = an atom that has __________one or more electrons (has less Protons than electrons)Ionization energy = the energy required to __________ an electron (“cationization energy”)Atomic radius = The ________(r) of an atom. The bigger and atom, the larger the radius. Radii = plural of “radius”Ionic radius = the _______of an ion

1. ATOMIC SIZE (atomic radius/radii

Increase as you go _________ a group ( electrons fill more and more higher energy levels as you move down – so the radius increases)

Decrease as you go ________ a period (inner shell electrons remain the same but Proton number increases. Shielding = outer shell electrons by the inner shell electrons from the attraction of the nucleus

When a neutral atoms gain an electron, its radius becomes _________( Ex: Cl atom smaller than Cl- anion. This is because Cl- has more electrons than protons so the outer-shell electrons are pulled in less than they are in the Cl atom)

2. Ionization energy

Ionization energy = the energy needed to _________ an electron from the valance shell of an atom (and Electronegativity) = increases across a period and up a group

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3. Ionic radii ( Ion size)

When a neutral atom ________ an electron its radius becomes smaller (Ex: Li atom is larger than Li+ cation that has lost an electron)

When a neutral atoms ________ an electron its radius becomes larger ( Ex: Cl atom smaller than Cl - anion. This is because Cl- has more electrons than protons so the outer-shell electrons are pulled in less than they are in the Cl atom).

4. Electronegativity

• Fluorine (F) is the _______electronegative element on the periodic table. Followed by O, then N and Cl.• In general, the electronegativity of an element __________ as one goes up a family. Electronegativity increases in the

order: I < Br < Cl < F.• Also, electronegativity ___________ as one goes across the table. Electronegativity increases in the order: B < C < N < O

< F.Summary of periodic trends

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