The Periodic Table of the Elements Video Notes

The Periodic Table of the Elements

Video Notes • Who is Dmitri Mendeleev? • What are the main groups of the periodic table? • How is the periodic table organized?

HISTORY • Created by Dmitri Mendeleev in 1869 • Mendeleev was so confident in his table that he used it to predict the physical properties of three elements that were yet unknown. • Organized in rows and columns

PERIODS • Period: horizontal row • The elements have the same number of atomic shells from 1 to 7 for its electrons

GROUPS • Groups: vertical columns • Elements in the same group have similar properties

FAMILIES • Elements are grouped together based on their properties

chlorine nitrogen gold silver mercury oxygen hydrogen helium sodium niobium neodymium carbon

Elements • Science has come along way since Aristotle’s theory of Air, Water, Fire, and Earth. • Scientists have identified 90 naturally occurring elements, and created about 28 others.

Elements • Element: any of more than 100 known substances that cannot be separated into simpler substances • The elements make up our world, our sun, and in fact, the entire universe

The most abundant element in the earth’s crust is oxygen.

3 Categories of the Periodic Table 1. Metals 2. Non-metals 3. Metalloids

3 Categories of the Periodic Table 1. Metals: • Good conductors of heat and electricity • Shiny, ductile, malleable • Reacts with water which results in corrosion • Almost 75% of all elements are classified as metals

3 Categories of the Periodic Table 2. Non-Metals: • Poor conductors of heat and electricity. • Brittle and break easily, dull • Many non-metals are gases. Flourine (Fl), Chlorine (Cl), Bromine (Br), Iodine (I), Astatine (At)

3 Categories of the Periodic Table 3. Metalloids/Semimetals: (metal-like) have properties of both metals and non -metals. • can be shiny or dull. • ductile and malleable. • Uses: computers, calculators and electronics

Practice Identifying Based on what you know AND this element’s place in the periodic table, what category is it? Metal, nonmetal or metalloid? 1. Oxygen – a gas, doesn’t conduct electricity well 2. Silver – shiny, malleable, conducts heat 3. Hydrogen – gas, first element on the periodic table Discuss with your group

YOUR PERIODIC TABLE!

Steps: 1. Create a key 2. Label the categories 3. Outline each category 4. Color