1. Chapter 12 Section 1 Arranging the Elements The Periodic Table Crash Course --- The Periodic Table

2. Why arrange the elements? Read page 336 Why would grouping elements by their properties help scientist? So they could understand how the elements interact with one another. What helped Mendeleev see the pattern of the elements? He arranged them in order of increasing atomic mass

3. Read p.337 What was seen when Mendeleev arranged the elements in order of increasing mass? He saw a repeating pattern What is the name of something that occurs or repeats at regular intervals? Periodic Who worked with the atomic number (number of protons) in atoms Henry Moseley

4. Properties p.340-341 MetalsNon-MetalsMetalloids WHERE Outer layer of electrons Describing words

5. MetalsNonmetalsMetalloids Where: To the left of the zigzag lineRight of the zigzag lineBorder the zigzag line Outmost electron layer: Few electrons in their outermost layer Almost complete set of electrons in their outermost layer Almost half of a complete set of electrons in their outermost layer Describing Words: Shiny, ductile, good convertors of electricity, malleable, and conduct thermal energy Brittle and can shatter, not shiny, poor conductors of energy Mostly shiny, can be brittle or hard, can conduct energy at high temps.

6. Decoding the periodic table Read p.342 What does a chemical symbol do? Identify the element How are chemical symbols written? With a capital letter and a lower case letter for the second letter if needed New elements are written how? With temporary 3 letter symbols

7. Periods What is a period in chemistry? A horizontal row of elements in the periodic table The physical and chemical properties in these rows follow what type of pattern? repeating

8. Columns What is a group? A vertical column of elements in the periodic table; elements in a group share chemical properties Why is a group sometimes called a family? Often, they have similar chemical and physical properties Bozerman Science --- A Tour of the Periodic Table Bozerman Science --- A Tour of the Periodic Table

9. Exit Slip On a slip of paper, answer the following questions: 1. How are the elements arranged in the modern periodic table? 2. A horizontal row of elements in the periodic table. 3. A column of elements is known as a family or a __________.