Cycle 6 Chemistry

Antoine Lavoisier

Antoine Lavoisier

French Scientist Made a list of all 33 known elements at that time Broke into 4 categories

What are the 4 categories Antoine Lavoisier designated the elements to?

Gases Metals Non-Metals Earths

Dimitri Mendeleev

Arranged elements by increasing mass and putting elements that shared properties in columns Realized that there were undiscovered periodic elements Considered the Father of the Periodic Table

Henry Mosely

Arranges Elements by Atomic Number Created the Periodic Law

Groups

Elements in the same vertical column Otherwise known as families Numbered 1-18

Periods

Elements in the same horizontal row Numbered 1-7

Representative Elements

Elements in groups 1,2, and 13-18 (The Main Points of Reference for what we are doing)

Periodic Law

States that there is a periodic repetition of physical and chemical properties of the elements when arranged according to increasing atomic number

What are elements arranged by?

Increasing atomic number

Valence Electrons

Defined as electrons in the outermost orbitals of the atom

Metals

Shiny Solid at Room Temperature Good Conductors of heat Most elements are metals

Non-metals

Elements that are generally gases or brittle Poor conductors

Metalloids

Have physical and chemical properties of both elements 8 Metals

Group 1

Alkaline Metals Very Reactive

Group 2

Alkaline Earth Metals Very Reactive

Transition Metals

Similar Properties to other metals but do act a bit differently due to their partially filled subshells

Inner Transition Metals

The two columns at the bottom of the periodic table Lanthanides Actinides

Group 17

Halogens Highly reactive Very Close to becoming Noble Gases

Group 18

Noble Gasses Unreactive In a perfect state of balance

How are Groups generally identified?

By the element at the top of the group Ex. Carbon Family

KNOW THE DIFFERENT BLOCKS

S, D, P, F

Ions

Atoms of an element which gained or lost electrons

Anions

Atoms that gain electrons and become negatively charged. More electrons than protons Atoms get bigger as they gain more electrons

Cations

Atoms that lose electrons and become positively charged. Atoms get smaller as they give away their valence electron. More protons than Electrons

Why do Ions form?

To help increase stability of the atoms

Atomic Radius

The size of the atom is influenced by the number of electrons that an atom has. Atomic size is determined by how close an atom is to its neighboring atom. Definition: Half the distance between two equidistance nuclei

How is there an increase in atomic radius?

The atomic radius increases as you go to the left in the periodic table and down.

What occurs with more added Electrons?

Larger Orbital Size More Electron shielding

Electronegativity

Indicates the relative ability of its atoms to attract electrons in a chemical bond

How is there an increase in electronegativity?

As you move more to the right and up.

Periodic Trend

Electronegativity increases as you move to the right More protons in the nucleus to attract electrons

Group Trend

Electronegativity increases as you go up Strong Attraction to electrons

Octet Rule

Atoms tend to gain, lose, or share electrons in order to achieve stability. Aka 8 valence electrons

Why is the Periodic Table called the Periodic Table?

This is because the Periodic Table is periodic, meaning there is a repeating pattern with it.

Ionic Bonds

IONIC BONDS FORM BETWEEN METALS AND NON-METALS Ionic Bonds from when atoms become ions

What are Ionic Compounds Called?

Formula Units

Formula Units

The chemical formula of anionic compounds that lists the ions in the lowest ratio that equals a neutral electric charge.

DO WE USE THE WORD MOLECULE

NOOOOOOOOOOOO

How are ions arranged?

In a Crystal Lattice Structure

Crystal Lattice Structure

A repeating pattern of positive and negatively charged ions

Qualities of the Crystal Lattice Structure

Maximizes attraction between positive and negative ions which equal strong bonds Presence of particular metal ions lead to different colors

How is the STRENGTH OF IONIC BONDS MEASURED???

LATTICE ENERGY DUE TO THE CRYSTAL LATTICE STRUCTURE

What does Lattice energy do?

Relates the size and charge of the ions to the energy level needed to make the bond

Coulombs Law

Relates attraction to size and charge. Smaller atoms can be closer together and form stronger bonds. Larger atoms form smaller bonds that are weaker

Ionic Solids

Do not conduct electricity Charged ions can't flow and make a current

Ionic Solutions

When dissolved in water, they become electrolytes Conduct electricity very well Ions are separated and mixed

Properties of Ionic Compounds

Melting Point- Temperature that solids turn to liquids Ionic compounds have a very high melting point because of strong ionic bonds Boiling Point- Temperature at which a liquid becomes a gas. Ionic Compounds have a high boiling point

Ionic Compound Properties

Hard- Ionic Compounds in the solid form are hard because of strong ionic bonds that hold them together Brittle- Ionic Solids, despite being hard, are brittle of impacted with enough force.

What occurs everytime there is a chemical reaction?

Bonds are broken or made energy is either absorbed or released

Endothermic

Energy is absorbed by the chemical reaction

Exothermic

Energy is released by the chemical reaction THE FORMATION OF IONIC BONDS ARE ALWAYS EXOTHERMIC

KNOW HOW TO DO NAMING, CRISS CROSS, ETC

TRASH

Polyatomic Ions

Ions made with more than one atom bonded together These ions are charged molecules Act as a group

Metallic Bonds

Metals are not ionically bonded but share several properties with ionic compounds. Metals are arranged in crystal lattice structures in their solid states. The attraction between the positive metal cations and the negatively charged sea of electrons

Electronic Sea Model

The primary explanation for metallic bonding. Metals are described as having Localized metal cations (positively charged) Delocalized valence electrons (negatively charged)

What does the Electron Sea Model propose?

All metals contribute to their valence electrons to form a sea of electrons. The delocalized electrons are free to move around the metal cations.

How is the strength of a metallic bond regulated?

Related to the number of valence electrons contributed by the metal atom. The more valence electrons, the stronger the metallic bond.

Malleable

Metals are able to be hammered or rolled into thin sheets Ex. Aluminum foil

Ductile

Metals are able to be drawn into thin wires

Alloys

Mixtures of metals that have unique properties.

Substitutional Alloys

Alloys capable of taking the place of other metals because of their similar properties

Interstitial Alloys

Intertwined within the solids. In the smaller places electrons would reside in, but not as small as an electron.

How does Electron Configurations relate to the Periodic Table?

The last number in an electron configuration will match up to whatever PERIOD an element is in.

Atomic Size

Defined by how closely an atom lies to a neighboring atom ATOMIC SIZE AND ATOMIC RADIUS ARE DIFFERNENT

What happens when atoms gain electrons?

They become bigger

Shielding

Involving the shielding of electrons and their charge from the nucleus of an atom.

Nuclear Charge

Can pull electrons closer to the nucleus of an atom. The stronger it is, the more electrons can be pulled.

Unit Cell

The smallest arrangement of atoms in a crystal lattice structure that has the same symmetry as the whole crystal; a small representative that is part of a whole