Why does the periodic table look the way it does?

Chemistry: Unit 5 Guided Notes

Academic Language:

Actinide SeriesAlkali metalAlkaline earth metalDuctileElectronegativityGroupHalogenInner transition metalIonIonization energyLanthanide seriesMalleableMetalMetalloidNoble gasNonmetalOctet rulePeriodPeriodic lawRepresentative elementTransition elementsTransition metals

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Unit 5 Homework:

CALM: http://calm.indiana.edu/

5.1 Development of the Modern Periodic Table:

5 questions

5.2 Classification of the Elements:

10 questions

5.3 Periodic Trends:

10 questions

5.4 ion Formation:

10 questions

5:5 Accumulating Content and Skills:

10 questions

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Chemistry Unit 5: Learning Goals and Objectives

5.1 Development of the Modern Periodic Table- The periodic table evolved over time as scientists discovered more useful ways to compare and organize the elements.

o Trace the development of the periodic table.o Identify key features of the periodic table.

5.2 Classification of the Elements –Elements are organized into different blocks in the periodic table according to their electron configurations.

o Explain why elements in the same group have similar properties.o Identify the four blocks of the periodic table based on their electron configuration.

5.3 Periodic Trends- Trends among elements in the periodic table include their size and their ability to lose or attract electrons.

o Compare period and group trends of several properties.o Relate period and group trends in atomic radii to electron configuration.

5.4 Ion formation – The loss or gain of an electron form an ions that then forms ionic bonds

o Learn the common list of cationso Learn the common list of anions

5:5 Accumulating Content and Skills:– Chemistry content is continuous and builds on prior knowledge and skills. This section will combine this unit with previous units.

Apply knowledge and skills from previous units to content learned in this unit.

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5.1 Development of the Modern Periodic Table- The periodic table evolved over time as scientists discovered more useful ways to compare and organize the elements.

Objective: Trace the development of the periodic table.

Development of the Periodic Table

In the 1700’s, Lavoisier compiled a list of all the known elements of the time.

The 1800’s brought large amounts of information and scientists needed a way to organize knowledge about elements.

Advent of electricity-

Development of the spectrometer

Industrial revolution

John Newlands proposed an arrangement where elements were ordered by increasing atomic mass.

Law of Octaves Newlands (1864) noticed when the elements were arranged by increasing atomic mass, their properties repeated every eighth element.

Octaves was used due to the musical analogy, but was widely dismissed.

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The Periodic Table

Meyer and Mendeleev both demonstrated a connection between atomic mass and elemental properties.

Mendeleev’s Table – a Russian scientist – gets the most credit because he published first.

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Moseley discovered that each element had a distinct number of protons.o

Periodic Law – the periodic repetition of chemical and physical properties of the elements when they are arranged by increasing atomic number.

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Objective: Identify key features of the periodic table.

The Modern Periodic Table contains

Periods - Rows of elements

Groups – Columns of elements

o Representative elements –

o Transition elements –

Types of Elements – Elements are classified as metals, non-metals, and metalloids.

Metals – are made up of most of the representative elements and all of the transition elements.

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Most are Ductile and Malleable – Ductile- Malleable-

o Alkali metals –

o Alkaline earth metals –

o Transition metals – (groups 3-12) d block are divided into transition metals and inner transition metals.

The two sets of inner transition metals (f block) are called the lanthanide series and actinide series and are located at the bottom of the periodic table.

Lanthanide series – are phosphors Actinide series – 2nd row of inner transition metals

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Nonmetals – are elements that are generally gases or brittle, dull-looking solids, and poor conductors of heat and electricity.

o Halogens –

o Noble gases –

Metalloids – also called semi-metals –

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5.2 Classification of the Elements –Elements are organized into different blocks in the periodic table according to their electron configurations.

Objective: Explain why elements in the same group have similar properties.

Organizing the Elements by Electron Configuration – electron configuration determines the chemical properties of an element.

o All group 1 elements have one valence electron.

o All group 2 elements have two valence electrons.

The energy level of an element’s valence electrons indicates the period on the periodic table in which it is found.

The number of valence electrons for elements in groups 13-18 is ten less than their group number.

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Objective: Identify the four blocks of the periodic table based on their electron configuration.

s, p, d and f block elements

o The d block contains the transition metals and is the largest block.o There are exceptions, but the d-block elements usually have filled

outermost s orbital, and filled or partially filled d orbital.

o The five d orbitals can hold 10 electrons, so the d-block spans ten groups on the table.

The f block contains the inner transition metals.

o The f block elements have filled or partially filled outermost s orbitals and filled or partially filled 4f and 5f orbitals.

o The 7 f orbitals hold 14 electrons, and the inner transition metals span 14 groups.

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5.3 Periodic Trends- Trends among elements in the periodic table include their size and their ability to lose or attract electrons.

Objective: Compare period and group trends of several properties.

Objective: Relate period and group trends in atomic radii to electron configuration.

Atomic Radius - is determined by the amount of positive charge in the nucleus and the number of valence electrons of an atom. It is usually measured in picometers (10-12).

For diatomic nonmetals, the atomic radius is the distance between nuclei of identical atoms.

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The periodic trend:

Valence electrons are not shielded from the increasing nuclear charge because no additional electrons come between the nucleus and the valence electrons.

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Ion – atom(s) that gain or lose one or more electrons to forma a net charge

Ionic Radius – The radius of an ion (charged atom)

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o Electrostatic repulsion between remaining electrons decreases and pulls closer to nucleus.

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Periodic Trend:

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Ionization Energy – energy needed to separate an electron from the positive charge of the nucleus of a gaseous atom. (how strongly a nucleus holds on to an electron

First ionization energy is the energy required to remove the first electron.

The ionization at which the large increase in energy occurs is related to the number of valence electrons.

Periodic Trend:

Octet rule: atoms tend to gain, lose or share electrons in order to obtain 8 valence electrons. The octet rule is useful for predicting what types of ions an element is likely to form.

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Electronegativity – its relative ability of its atoms to attract electrons in a chemical bond. Measure in Paulings: numbers 4 and less.

Periodic Trend:

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5.4 Ion formation – The loss or gain of an electron form an ions that then forms ionic bonds

Objective: Learn the common list of cations

Cations – are atom or groups of atoms that have lost electrons

Cations

Ag+ Silver Hg2+ Mercury (II)Al3+ Aluminum Hg2

2+ Mercury (I)Au+ Gold (I) K+ PotassiumAu3+ Gold (III) Li+ LithiumBa2+ Barium Mg2+ MagnesiumBe2+ Beryllium Mn2+ Manganese (II)Ca2+ Calcium Mn3+ Manganese (III)Co2+ Cobalt (II) Na+ SodiumCo3+ Cobalt (III) NH4

+ AmmoniumCr2+ Chromium (II) Ni2+ Nickel (II)Cr3+ Chromium (III) Ni4+ Nickel (IV)Cs+ Cesium Pb2+ Lead (II)Cu+ Copper (I) Pb4+ Lead (IV)Cu2+ Copper (II) Ra2+ RadiumFe2+ Iron (II) Rb+ RubidiumFe3+ Iron (III) Sn2+ Tin (II)H+ Hydrogen Sn4+ Tin (IV)H3O+ Hydronium Sr2+ Strontium

Zn2+ Zinc

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Objective:Learn the common list of anions

Anions – are atom or groups of atoms that have gained electrons

Anions

As3- Arsenide MnO4- Permanganate

Br- Bromide N3- NitrideBrO- Hypobromite NH2

- AmideBrO3

- Bromate NO2- Nitrite

C2H3O2- Acetate NO3

- NitrateC2O4

2- Oxalate O2- OxideHC2O4

- Hydrogen oxalate O22- Peroxide

Cl- Chloride OH- HydroxideClO- Hypochlorite P3- PhosphideClO2

- Chlorite PO43- Phosphate

ClO3- Chlorate HPO4

2- Monohydrogen phosphateClO4

- Perchlorate H2PO4- Dihydrogen phosphate

CN- Cyanide Se2- SelenideCO3

2- Carbonate S2- SulfideHCO3

- Hydrogen carbonate SO32- Sulfite

CrO42- Chromate SO4

2- SulfateCr2O7

2- Dichromate HS- Hydrogen sulfideF- Fluoride HSO3

- Hydrogen sulfiteH- Hydride HSO4

- Hydrogen sulfateI- Iodide Te2- TellurideIO- HypoioditeIO4

- Periodate

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5:5 Accumulating Content and Skills:– Chemistry content is continuous and builds on prior knowledge and skills. This section will combine this unit with previous units.

Objective: Apply knowledge and skills from previous units to content learned in this unit.

o How does the electron configuration of an atom relate to ion formation?

o How do chemical and physical properties relate to periodic trends? What other properties might have periodic trends?

o What does a group tell us about valence electrons and ion formation?

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