Objectives  SWBAT analyze the importance of periodic law.  SWBAT distinguish their family from the rest on the periodic table. Catalyst  Get into groups and organize the elements in order of increasing mass, and also line up the shading.

Today’s Agenda  Catalyst  How is the periodic table organized?  Intro Periodic Table Project  Unlock the first secrets of the periodic table  Group work time  Exit Question

First things first… You are about to begin a journey to find the secrets of the Periodic Table The Periodic Table is a majestic tool used by scientists all over the world Are you ready? Let’s go.

How is it organized?  Each group will receive a baggie of periodic table pieces  With your group, organize the pieces in a logical way  Be ready to explain HOW you organized the pieces

Now…  Organize the pieces in order of increasing atomic mass  Also, line them up according to shading

What’s missing? Ga Ge These elements were also missing when scientists were putting the periodic table together!

The Periodic Table Key Point #1: The periodic table organizes the elements into many different groups based on physical and chemical properties.  We will learn about the major ways to group the elements – by…  Family  Metals/metalloids/nonmetals  Valence Electrons  Atomic size  Electronegativity

What does PERIODIC mean? Key Point #2: Periodic means that there is some kind of pattern.  In the Periodic Table, there are numerous patterns  What about in regular life? How could you group the following items in different ways?

The Evolution of the Periodic Table  Just like atomic theory, the Periodic Table also has a long history  In the late 1790s, French scientist Antoine Lavoisier compiled a list of elements known at that time - only 23!  In the 1800s, scientists began discovering a ton of elements - up to 70!

Evolution Continued New elements meant new data! Scientists needed a way to organize everything!

John Newlands (1860s)  Arranged the Periodic Table by increasing ATOMIC MASS  Noticed patterns based on physical and chemical properties - repeated every 8th element  Law of Octaves

Newland’s Periodic Table Law of Octaves

Mendeleev (1869)  A rranged elements by increasing ATOMIC MASS into columns based on chemical and physical properties  Left spaces for undiscovered elements  First to publish table

Mendeleev’s Periodic Table EMPTY SPACES!

Mosely (1913)  Arranged elements by increasing ATOMIC NUMBER  Some of Mendeleev’s elements in the wrong order  Periodic Law

Our Periodic Table – Thanks to Mosely

Periodic Law  Periodic Law is the statement that there is a periodic (patterned) repetition of chemical and physical properties of the elements when they are arranged in increasing atomic number

Periodic Table Review 1. Why is the periodic table called the “periodic” table? 2. How did Newlands organize the periodic table? 3. Who published the first periodic table? 4. Who developed periodic law?

Basic Terms to Know Write these in your notes to remember!  Period – horizontal rows on periodic table  Family/Group – vertical columns on periodic table

Metals, Metalloids, and Nonmetals

Major Families Alkali Metals Alkaline Earth Metals Transition Metals Halogens Noble Gases Lanthanides Actininides H BeBCNOF He Ce Th

Alkali Metals Alkali metals are very reactive – even with water! Sodium + Water  EXPLOSION!EXPLOSION

Alkaline Earth Metals  Alkaline Earth metals are also very reactive  Shiny solids that are harder than Alkali metals  Alkaline Earth Metal Spotlight: CALCIUM  Calcium is essential for human life, especially in maintaining bones and teeth  Found widely in nature combined with oxygen  Abrasives in toothpaste and emery boards  Magnesium Demo!

Boron’s Group  Gallium is a silver metal that literally melts in your hand! Don’t try this yourself!

Carbon’s Group  Carbon is one of the most important elements on Earth!  There is a whole branch of chemistry dedicated to studying carbon – ORGANIC CHEMISTRY!  If you are a science major in college, you will most likely take Organic  Silicon is the second most abundant element on Earth!  Use in computer chips and solar cells  Found in quartz, sand, and glass

Nitrogen’s Group  Metals, nonmetals, and metalloids!  Nitrogen, which you breathe, can form some of the most explosive compounds known to man  Arsenic is a toxic substance that was used to treat some illnesses back in the day  Bismuth is used in fire sprinklers

Oxygen’s Group  Oxygen  We must breathe oxygen to survive…so it’s pretty important  Reacts with some of the noble gases  Sulfur  Hydrogen sulfide smells like rotten egg  Selenium  Used in solar panels because it can convert light into energy

 Fluorine (really fluoride) is added to toothpaste  Chlorine gas is a deathly green gas that was first used as a form of chemical WARFARE in WWII Halogens (Fluorine’s Group)

Noble Gases (Helium’s Group)  Noble gases do not react with other elements very often – they are already “happy”  They can be called “inert” because they don’t react  Neon is used in neon lights  Helium Voice! Helium Voice

Transition Metals  Conduct electricity  Can form different ions (We’ll learn more about ions later!)  Many found in nature – found all over the world (map on page 200)  Uses  Found in alloys, wires, plastics, etc.  Your body needs trace (small) amounts many of them

Research Time  Pick your group’s family  Start researching info about your family  Chapter 7 in your book contains information about each family

Exit Question 1. Why is the periodic table called the “periodic” table? 2. What is your group’s family? List two characteristics of elements in your group’s family. Homework: Periodic Table Assignment