Matter+and+Periodic+Table

Matter and Periodic Table Editor: Julia McNamara



**GLOSSARY** ** Alkali Metal **: Any metal in Group 1A of the period ic table ** Alkaline Earth Metal **: Any metal in Group 2A of the period ic table. ** Atomic Radius **: A term used to describe the size of the atom. ** Chemical Property **: The ability of a substance to undergo a specific chemical change. ** Chemical Reaction **: A change in which one or more reactant s change into one or more product s; characterized by the breaking of bonds in reactant s and the formation of bonds in product s. ** Chemical Symbol **: The 1 or 2 letters that stands for a specific element. In most cases, the first letter (ex. H=Hydrogen), the first letter and the second heard letter (ex. Co=Cobalt), or the significant letters to the element 's name usually in Latin or Greek (ex. Silver=Ag because the latin term is Argentum). ** Distillation **: is a method of separating mixtures base d on differences in their volatilities in a boiling liquid mixture. Distillation is a unit operation, or a physical separation process, and not a chemical reaction. ** Element **: An element is a pure substance that cannot be broken down into any simpler substance s by //chemical// methods. In that light, an element is the simplest kind of matter. ** Ionization Energy **: an atom or mole cule is the minimum energy required to remove (to infinity) an electron from the atom or mole cule isolated in free space and in its ground electronic state. gas, a liquid does not disperse to fill every space of a container, and maintains a fairly constant density. different from states of matter. The states of matter (e.g., liquid, solid , gas ) //are// phase s, but matter can exist in different phase s yet the same state of matter. For example, mixtures can exist in multiple phase s, such as an oil phase and an aqueous phase. ** Physical Change **: a change during which some properties of a material change, but the composition of the material doesn't change new compound s in a chemical reaction. ** Volume **: the amount of space, measured in cubic units, that an object or substance occupies; a mass or quantity
 * Anion : ** Any atom or group of atoms with a negative charge.
 * Cations : ** Any atom or group of atoms with a positive charge.
 * Chemical Change **- A change that produces matter with a different composition than the original matter.
 * Compound : ** a pure substance composed of two or more element s whose composition is constant.
 * Electronegativity : ** The ability of an atom to attract electrons when the atom is in a compound.
 * Extensive Property : ** A property that depends on the amount of matter in a sample. Examples: Mass and Volume
 * Filtration : ** A process that separates a solid from the liquid in a heterogeneous mixture
 * Gas : ** A form of matter that takes the shape and volume of its container; has no definite shape or volume.
 * Group : ** A vertical column in the period ic table. There are 18 of them. Element s in a group have configurat ions that are alike in terms of the outermost electron shells of their atoms.
 * Halogens : ** A nonmetal in Group 7A of the period ic table.
 * Heterogeneous : ** Visibly consisting of different components.
 * Homogeneous : ** A mixture that is uniform in composition; components are evenly distributed and not easily distinguished.
 * Inner Transition Metal : ** An element in the lanthanide or actinide series; the highest occupied s sublevel and nearby f sublevel of its atoms generally contain electrons; also called inner transition element
 * Intensive Property : ** A property that depends on the type of matter in a sample, not the amount of matter in the sample.
 * Ions : ** an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation (positive ion), which is created by electron loss and is attracted to the cathode in electrolysis, or as an anion (negative ion), which is created by an electron gain and is attracted to the anode. The valence of an ion is equal to the number of electrons lost or gained and is indicated by a plus sign for cat ions and a minus sign for an ions, thus: Na + , Cl−, Ca ++ , S =.
 * Law of Conservation : ** In any physical change or chemical reaction, mass is conserved. Mass can not be created or destroyed.
 * Liquid -** Liquid is one of the three classical states of matter. Like a gas, a liquid is able to flow and take the shape of a container, but, like a solid , it resists compression. Unlike a
 * Mass : ** A measure of the amount of matter that an object contains. The SI unit of mass is the kilogram.
 * Metalloids : ** A Metalloid is a nonmetallic element that has some properties of a metal.
 * Metals : ** One of a class of element s that are good conductors of heat and electric current; they are ductile (can be drawn into wires), malleable (hammered into thin sheets without breaking), and shiny
 * Mixture : ** a substance consisting of two or more substance s mixed together (not in fixed proport ions and not with chemical bonding)
 * Noble Gases : ** An element in Group 8A of the period ic table; the //**s**// and //**p**// sublevels of the highest occupied energy level are filled
 * Nonmetals : ** An element that tends to be a poor conductor of heat and electric current; nonmetals generally have properties opposite to those of metals.
 * Period : ** A horizontal row of element s in the period ic table.
 * Periodic Law : ** when the element s are arranged in order of increasing atomic number; there is a period ic repetition of their physical and chemical properties
 * Phase : ** a physically distinctive form of matter, such as a solid, liquid , gas or plasma. A phase of matter is characterized by having relatively uniform chemical and physical properties. Phase s are
 * Physical Property : ** A quality or condition of a substance that can be observed or measured without changing the substance 's composition.
 * Precipitate : ** A solid that forms and settles out of a liquid mixture.
 * Product : ** A substance produced in a chemical reaction.
 * Reactant : ** A reactant is present at the start of a chemical reaction . They appear on the left side of a chemical reaction, and they are the element s and compound s that react to form
 * Representative Elements : ** An element in an "A" group in the period ic table; as a group these element s display a wide range of physical and chemical properties. In their atoms, the "s" and "p" sub levels in the highest occupied energy level are partially filled.
 * Solid : ** A form of matter that has definite shape and volume . Particles in a solid are tightly packed together and solid s expand slightly when heated. Solid s also are incompressible (can't decrease its volume ).
 * Solution : ** A homogeneous mixture  made of two or more substance s and where a solute is dissolved in another substance, called the solvent.
 * Substance : ** Matter that has a uniform and definite composition. Called either an element, a compound , or a pure substance.
 * Transition Metals : ** One of the Group B element s in which the highest occupied //s// sub level and a nearby //d// sub level generally contain electrons.
 * Vapor : ** is a substance in the gas phase at a temperature lower than its critical point

Team 1


Co Editor: Kelsey Sullivan
Group: Colleen Fitzgerald, Shannon Degnan, Abby John, Lindsey Bedrosian, Hannah Valley, David O' Brien

Properties of Matter
By: Colleen Fitzgerald

Describing Matter Identifying Substances Physical Property States of Matter Physical Changes
 * Extensive property-property that depends on the amount of matter in a substance (Ex. volume or mass)
 * Intensive property depends on the type of matter in a sample.
 * Substance- matter with a uniform and definite composition
 * Has identical intensive and extensive properties
 * Ex. Gold and copper have the same properties in common but are different in terms of how they conduct heat, how hard they are, what color they are, and how malleable they are)
 * A quality or condition of a substance that can be observed or measured without changing the substances composition
 * Ex. Melting point, boiling point, state, and color
 * There are three forms of matter:
 * Solid- definite shape and volume, not easily compressed
 * Liquid-indefinite shape but definite volume, not eaisly compressed, takes the shape of the container in which its placed
 * Gas- indefinite shape and volume, take the shape and volume of its container, and is not easily compressed
 * Gases and vapors- A gas is a gas at room tempurature but a vapor is usally a liquid or solid at room tempurature[[image:http://myweb.cwpost.liu.edu/vdivener/notes/solid-liquid-gas.gif width="216" height="283" align="right"]]
 * Porperties of the material change but not its composition
 * Ex. boiling, melting, freezing, and condensation
 * Can either be reversible or irreversible
 * Reversible- change from one state to another (Ex. cooling a liquid to become a soild again)
 * Irreversible- you can't get back the original state of the substance( Ex.cutting hair or cracking an egg)

Mixtures
By: Shannon Degnan and Abigail John Mixture Heterogenous mixtures Homegenous mixtures
 * A physical blend of two or more components is a mixture
 * Most samples of matter are mixtures
 * Mixtures can be heterogeneous or homogeneous
 * A mixture in which the composition is not uniform throughout
 * A mixture in which the composition is uniform throughout
 * Another name for a homogenous mixture is a solution
 * The term phase describes any part of a sample with uniform composition and properties

Heterogeneous mixture Homogeneous mixture

Separating Mixtures

 * ﻿To separate olive oil and vinegar, for example, you could just pour off the layer of oil
 * You could also cool a mixture

Filtration

 * <span style="color: #0e060e; font-family: Arial,Helvetica,sans-serif;">The process that separates a solid from a liquid in a heterogeneous mixture is called <span style="color: #1a8b93; font-family: Arial,Helvetica,sans-serif;">filtration

<span style="color: #ef57ec; font-family: 'Comic Sans MS',cursive;">Distillation

 * <span style="color: #091011; font-family: Arial,Helvetica,sans-serif;">﻿Tap water is a homogeneous mixture of water and other substances that dissolved in water
 * <span style="color: #091011; font-family: Arial,Helvetica,sans-serif;">One way to separate the other components is through <span style="color: #3ca0af; font-family: Arial,Helvetica,sans-serif;">distillation
 * <span style="color: #091011; font-family: Arial,Helvetica,sans-serif;">During <span style="color: #3b8691; font-family: Arial,Helvetica,sans-serif;">distillation <span style="color: #091011; font-family: Arial,Helvetica,sans-serif;">, a liquid is boiled to produce a vapor that is then condensed to a liquid

Section 2.3: __Elements__ and __Compounds__
By: Lindsey Bedrosian and Hannah Valley

<span style="color: #e04d9c; font-family: Arial,Helvetica,sans-serif;">Symbols and Formulas(Hannah Valley)

 * Chemists use chemical symbols to represent elements, and chemical formulas to represent compounds
 * Many symbols used today are elements based on a system developed by Swedish Chemist Jons Jacob Berzelius
 * He based the symbols on the Latin names for the elements
 * Each element is represented by a one- or two-lettered **chemical symbol**
 * First letter is always capitalized, second is not
 * Chemical symbols provide a short-hand way to write the chemical formulas of compounds
 * Ex: the chemical symbols for hydrogen, oxygen and carbon are H, O and C. the formula for water is H(2)O. The formula for table sugar is C12-H22-O11.
 * Subscripts ( like the 2 in H2-O) are used to indicate the relative proportion of the elements in the compound
 * Ex: the subscript 2 in H2-O mean that there are always two parts of Hydrogen for each part of Oxygen in water.
 * Because an element always has a fixed composition, the formula for a compound is always the same

<span style="color: #ff00ff; font-family: Arial,Helvetica,sans-serif; font-size: 90%;">Distinguishing Elements and Compounds(Lindsey Bedrosian) <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> I. Element vs. Compound <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> A. Element <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> 1. The simplest form of matter that had a unique set of properties <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> a. Ex.- Oxygen and hydrogen <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> B. Compound <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> 1. A substance that contains two or more elements chemically combined in a fixed proportion <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> a. Ex- Sucrose <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> C. Compounds can be broken down, elements cannot <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> II. Breaking Down Compounds <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> A. Chemical Change <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> 1. A change that produces matter with a different composition then the original matter <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> a. Ex. Heating is a process to breakdown compounds <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> III. Properties of Compounds <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> A. Compounds have very different properties than their elements <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> IV. Distinguishing Substances and Mixtures <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> A. If the composition of a material is fixed, the material is a substance <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;"> B. If the composition of a material may vary, the material is a mixture

Chemical Reactions
by: David O'Brien 2.4 Chemical Reactions p. 53-56

Chemical Changes

> ex.)Iron + Oxygen = Rust (the ability to rust is a chemical property of iron) Recognizing Chemical Changes
 * The ability of a substance to undergo a specific chemical change is called a chemical property
 * Chemical properties can only be seen when a chemical reaction occurs
 * During a physical change the makeup of matter never changes
 * During a chemical change the makeup of matter always changes
 * Chemical Change = Chemical Reaction
 * Chemical Reaction: one or more substances change into a new substance
 * Reactant = substance present at beginning of chemical reaction
 * Product = the new substance created through the reaction

> 1: change in energy > 2: change in color > 3: production of a gas > 4: creation of a precipitate > Conservation Of Mass
 * Four clues to recognize a chemical change
 * Precipitate = a solid that settles and forms out of a liquid mixture
 * Law of Conservation of Mass = mass stays consistent throughout both physical and chemical changes
 * Mass is neither created or destroyed during these changes

<span style="color: #000000; font-family: Georgia,serif;">Co Editor: Erika Paiva
<span style="color: #000000; font-family: Georgia,serif;">Group: Erika Paiva,Marybeth Nametz, Emily Taylor, Kim Kogot, Lauren Altmeyer, Mark Cuddy

Searching For an Organizing Principle
By: Erika Paiva pg. 155 - Since the 1700's, only thirteen elements have been identified. - Chemists had suspected that there were more elements to be discovered and they even assigned names to the elements, but they couldn't isolate the elements from their compounds. - During 1765-1775 Chemists discovered five new elements ( the three colorless gases were: hydrogen, nitrogen, and oxygen.) - The Scientific Method was a great way to search and discover new elements. - Still, it was so hard for the Chemists to know if they discovered all the elements. -Chemists came up with a logical and practical way to organize the elements. - J. W. Dobereiner - was a German chemists who in 1829 published a classification system. He grouped the elements in sets of three elements which all had similar properties, known as a **__triad__**. - One element in each triad had properties whith values that were extremely simialr to the other two elements. - The triad also had similar chemical properties. ( elements were grouped according to similar properties.) - Now, chemists know that all the elements can not be grouped into triads. - Another chemist was extremely dedicated to figuring out a way to arrange all of the elements, this man was known as __**Dmitri Mendeleev.**__

Mendeleev's Periodic Table
By: Marybeth Nametz pg. 156

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 80%;">Dmitri Mendeleev <span style="color: #ff00ff; font-family: 'Comic Sans MS',cursive; font-size: 130%;">Who was Dmitri Mendeleev? //<span style="font-family: Arial,Helvetica,sans-serif; font-size: 80%;">*Later that year, German chemist Lothar Meyer published a table of elements that was almost identical to Mendeleev's however Dmitri Mendeleev received more credit because he was the first to publish his table and his was more understandable. //
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;">**Dmitri Mendeleev** was a Russian chemist and teacher who in **1869 published a table of the elements***.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 90%;">His table of elements was **later developed ito the modern periodic table**

<span style="color: #ff00ff; font-family: 'Comic Sans MS',cursive; font-size: 130%;">Ho﻿w did Mendeleev develop and organize his table of elements?
//<span style="color: #bf500d; font-family: 'Comic Sans MS',cursive; font-size: 130%;"> <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 80%;">Early Image of Mendeleev's Periodic Table // <span style="color: #ff00ff; font-family: 'Comic Sans MS',cursive; font-size: 130%;">Other accomplishments of Mendeleev and his table of elements?
 * <span style="color: #0384c4; font-family: 'Comic Sans MS',cursive; font-size: 90%; line-height: 0px; overflow: hidden;">﻿ <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%; line-height: 0px; overflow: hidden;">Mendeleev first developed his table w hile he was trying to find a way to show the relationships among 60 elements for his students
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%; line-height: 0px; overflow: hidden;">He had written the properties of each different element on seperate note cards
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%; line-height: 0px; overflow: hidden;">Mendeleev moved each card around into a periodic table
 * Elements in a periodic table are arranged into groups that are based on a set of repeating properties
 * Mendeleev arranged the elements in his periodic table in order of increasing atomic mass**
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%;">On one of his earliest versions of the periodic table, Mendeleev left two spaces between zinc (Zn) and arsenic (As)
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%;">Left these spaces because he knew that bromine belonged with chlorine and iodine
 * //<span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%;">Mendeleev correctly predicted that additional elements would be discovered and would fill those spaces and closely predicted the properties of those elements based on their locations in the table of elements //
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%;">These elements between zinc and arsenic were **gallium** and **germanium** (discovered in 1875 and 1886)
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif; font-size: 90%;">The closeness of Mendeleev's prediction of properties and actual properties of the elements helped scientists to conclude that Mendeleev's periodic table was a powerful tool

Periodic Law
By: Emily Taylor pg. 157
 * Mendeleev developed his periodic table before scientists knew about the structure of atoms.
 * He didn't know that each atom of each element had a different number of protons, which is the atomic number.
 * 1913 - Henry Moseley (British) found an atomic number for each known element.
 * In the modern periodic table that we use today, elements are arranged in the order of increasing atomic number.
 * There are seven rows, or periods, in the periodic table which correspond to a principal energy level.
 * There are more elements in higher numbered periods because there are more orbitals(regions of space in which there is a high probability of finding an electron) in higher energy levels.
 * Elements in the same column, or group, have similar properties which change as you go from left to right across each group of the period table.
 * The pattern of properties within a period(row) repeats as you move across the table, left to right.
 * This pattern created the **periodic law** which says: When elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties.

Metals, Nonmetals, Metalloids
By: Kim Kogot pg. 158-160

Metals: -About 80% of elements on the periodic table are metals. -Metals are good conductors of heat and electricity. -Characteristics of metals include a lust or sheen (shiny surface), ductile (can be bent into wires) and malleable (can be hammered into thing sheets without breaking). -All metals are solids at room temperature except for Mercury.

Nonmetals: -Most are gases at room temperature (noble gases), a few are solids (sulfur and phosphorus). Only one element, bromine, is a liquid at room temperature. -Their properties are opposite that of metals; poor conductors of heat and electricity (carbon being the only excpetion), and solids are mostly brittle.

Metalloids: -Have some properties similar to a metal and/or nonmetal. -Metal or nonmetal behavior depends on environment and conditions. -Example: Silicon is a poor conductor of electricity unless it is mixed with boron.

Squares in Periodic Table
By: Alex Fischbach pg. 161



Squares in the Periodic Table - Periodic table – Symbols and names of elements. Classes&Groups è Structure of their atoms è Center – Symbol è Underneath symbol - name and atomic mass è Electrons in each energy level – vertical column near the atomic number è Atomic number – Underneath the element’s name. Elements are written in order of the increasing atomic number [ex. Hydrogen’s atomic # is 1, there for it is first] - Atom size decreases as you move from left to right across the table and increases as you move down a column - **Period** = the period number of an element shows the highest unexcited energy level for an electron in that element. - **Group =** are elements have the same outer electron arrangement - Black symbol = solid at room temperature - Red = Gas - Blue = Liquids at room temperature - Green = not found in nature - Periodic trends è Atomic size, ions, ionization energy, electric size, and electronegativity. - Background colors è Distinguish groups - Nonmetals = unique names Ex: Halogens - 2 Groups: O Alkali Metals O Alkaline Earth Metals O Other Metals O Metalloids O Nonmetals O Noble Gases [Representative Elements] O Transition Metals O Inner transition metals [Transition Elements]

Electron Configuration
By: Lauren Altmeyer pg.164 -Electrons play a key role in determining the properties of element -Elements can be sorted into: 1) Noble Gases 2) Representative Elements 3) Transition Metals 4) Inner Transition Metals Noble Gases -The elements in group 8A of the periodic table

-The first 4 noble gases are: Representative Elements -Shows the portion of the periodic table containing Groups 1A-7A -Elements in these groups are often referred to as representative elements because the display a wide range of physical and chemical properties -Most are solids, a few are gases, and one (Bromine) is a liquid -For any representative element, its group number=the number of electrons in the highest occupied energy level
 * Helium (He)
 * Neon (Ne)
 * Argon (Ar)
 * Krypton (Kr)



** Transition Elements **
By: Mark Cuddy pg. 166

Quick Facts: Transition Metals are... - B Group elements that provide a connection between the elements on either side of the Periodic Table (PT) - 2 Types: Transition and Inner Transition, classified by there electron configurations Examples of TM's: Gold, Copper, Silver, Iron

TRANSITION METALS INNER TRANSITION METALS Blocks of Elements Electron configurations and the position of elements in the periodic table bring about another pattern in the PT. The PT is divided into blocks that correspond to the highest occupied sublevels. TM's are in block //d// and ITM's in block //f.//
 * Displayed in main body of PT
 * In the atoms, the highest occupied s sublevel and a nearby f sublevel generally contain electrons
 * Characterized by electrons in d orbitals
 * Displayed below main body of PT
 * In the atoms, the highest occupied s sublevel and a nearby f sublevel generally contain electrons
 * Characterized by f orbitals that contain electrons




 * Each period on the PT corresponds to a principle energy level
 * EXAMPLE: period 4 elements have 3 full energy levels plus another
 * For TM's electrons are added to are added to a d sublevel for a principle energy level that is one less than the period number
 * For ITM's the principle energy level of the f sublevel is two less.

<span style="color: #0000ff; font-family: Georgia,serif; font-size: 200%;">Team 3
===<span style="color: #0000ff; font-family: Georgia,serif; font-size: 200%; line-height: 0px; overflow: hidden;">﻿ <span style="color: #000000; font-family: Georgia,serif; line-height: 0px; overflow: hidden;">Co Editor: Anne O' Toole ===

<span style="color: #000000; font-family: Georgia,serif; line-height: 0px; overflow: hidden;">Group: Lauren Bedard, Brendan Lynch, Erin Gareity, Anne O' Toole, Meghan Faber, Grace Rose

By: Lauren Bedard and Brendan Lynch

 * Molecules
 * units formed when atoms of the same element are joined to one another
 * Atomic radius
 * 1/2 of the distance between the nuclei of 2 atoms of the same element when the atoms are joined
 * measured in picometers
 * There is a very small distance between atoms in a molecule
 * Atomic size
 * increases: top to bottom within a group
 * decreases: left to right across a period

Group Trends in Atomic Size:

 * Atomic number increases within a group, charge on nucleus increases, number of occupied energy levels increases
 * Increase in positive charge causes electrons closer to nucleus
 * Increase in occupied orbital sheilds electrons in highest occupied energy level from attraction of protons in nucleus

Periodic Trends in Atomic Size:
Ions: Cation: Anion:
 * Shielding effect is constant for all elements in a period
 * Increasing nuclear charge pulls electrons (in highest occupied energy level) to nucleus causing atomic size to decrease
 * An ion is an atom, or group of atoms that has a positive or negative charge.
 * An atom is electrically neutral because it has an equal number of protons and electrons.
 * Positive and negative ions form when electrons are transferred between atoms.
 * Atoms of metallic elements, such as sodium, tend to form ions by losing one or more electrons from their highest occupied energy levels.
 * Atoms of nonmetallic elements, such as chlorine, tend to form ions by gaining one or more electrons.
 * A cation is an ion with a positive charge.
 * The charge for a cation is written as 1+, however the 1 is usually omitted. Ex. Na+ is equivalent to Na1+.
 * An anion is an ion with a negative charge.
 * The charge for an anion is written as 1-, however the 1 is usually omitted. Ex. Cl- is equivalent to Cl1-.

By: Anne O'Toole
First Ionization Energy Versus Atomic Number: By: Erin Garrity -ions are atoms or group of atom that has a positive or negative charge -atoms are only neutral when the number of protons and electrons is the same -the positive or negative charge is caused when electrons are either taken on or given away - a positively charged ion is called a cation -positive charge can be represented with a + -a negatively charged ion is called a anion -negative charge can be represented with a -
 * electrons can move to higher energy levels when atoms absorb energy
 * energy required to remove an electron from an atom is called **ionization energy**
 * ionization energy is measured when an element is in it gaseous state
 * the energy required to remove the first electron from an atom is called the first ionization energy
 * the cation produced has a 1+ charge
 * the second ionization energy is the energy required to remove an electron from an ion with a 1+ charge
 * the ion produced has a 2+ charge
 * the third ionization energy is the energy required to remove an electron from an ion with a 2+ charge
 * the ion produced has a 3+ charge
 * ionization energy can help you predict what ions elements will form
 * the first ionization energy decreases from top to bottom within a group
 * the first ionization energy of representative elements tends to increase from left to right across a period

Electronegativity pg 175-178 By: Meghan Faber and Grayce Rose

= ** Trends in Ionic Size ** =

By: Grayce Rose
 * During reactions between metals and nonmetals, nonmetal atoms usually gain electrons, andmetal atomsusually loose them: this effects ions that form as a result
 * **Cations** are smaller than the atoms they form
 * **Anions** are larger than the atoms they form
 * In metals, the ion is usually larger than the atom
 * Metals usually loose their outermost layer of electrons during ionization: the ion has one less occupied energy level
 * In nonmetals, the ion is usually larger than the atom: as the number of electrons increases, the attraction of the nucleus for any one electron decreases

Trends in Ionic Size on the Periodic Table:



= ** Trends in Electronegativity ** =

By: Meghan Faber
 * compounds can have two types of bonds
 * electrons are present in both types
 * **Electronegativity** is "the ability of an atom of an element to attract electrons when the atom is in a compound." It can be used to predict the bond of a compound.
 * The noble gases don't have many compounds, so they are not included.
 * The electronegativity is measured in Paulings, named after Linus Pauling who defined electronegativity.
 * Electronegativity values usually decreases from top to bottom (column), and increases left to right (period).
 * Metals:Lower electronegativity values
 * Nonmetals: high electronegativity values
 * Least electronegative: Cesium
 * Most electronegative: Fluorine

Electronegativity Values of Elements: