Intro to Chemistry

Atom Molecule WRITE Element Compound The smallest part of an element which still have the chemical properties of that element. WRITE Molecule The smallest physical unit of an element or compound, made of one or more identical atoms (in an element) or two or more different atoms (in a compound). Element A substances that cannot be separated into simpler substances by chemical means . Compound A pure substance composed of two or more elements whose composition is constant.

ELEMENTS are the basic building blocks from which everything is made. They are pure substances, and not made of other things that have been combined. WRITE WRITE

The ancient Greeks believed there were only 4 elements WRITE A IR Everything in the world is made up of 4 Elements. F IRE They were wrong. E ARTH W ATER

Remember, people believed that everything in the world was made up of 4 basic elements. FIRE WATER EARTH AIR

Let’s look at a tree. The tree is made of earth, air and water Let’s look at a tree. The tree is made of earth, air and water. Fire will destroy it. Everything in the world was made of these 4 elements combined in different amounts. WATER AIR EARTH FIRE

A F E W A FEW Elements WRITE AIR EARTH FIRE WATER An easy way to remember the original ELEMENTS is that were only A FEW elements. A FEW Elements WRITE FIRE WATER EARTH AIR A F E W

Today we know there are about 114 elements, and the same rules apply… They are pure substances, not made of other things that have been combined.

What does an Atom look like ? DRAW

What does an Atom look like ? DRAW - - + + - - - + + +

What does an Atom look like ? DRAW

What does an Atom look like ? DRAW

What does an Atom look like ? WRITE DRAW We call this an Electron Cloud

_ + WRITE Electrical Name of Charge Particle Location Size Nucleus Proton Nucleus 1 A.M.U. Neutron Nucleus 1 A.M.U. Neutral _ So small we can call it Somewhere outside the Nucleus Electron WRITE

The number of Protons + Neutrons

Let’s look at the Periodic Table When looking at an Element on the Periodic Table, we can get a lot of information. 13 Al Aluminum 17 WRITE DRAW

Let’s look at the Periodic Table When looking at an Element on the Periodic Table, we can get a lot of information. 13 Atomic Symbol Can be 1, 2 or 3 letters. The first letter must always be a capital, and the rest must always be lower case. Al Name of Element Aluminum 17 WRITE

Al 13 17 Let’s look at the Periodic Table Aluminum WRITE When looking at an Element on the Periodic Table, we can get a lot of information. 13 Atomic Weight This represents the number of protons PLUS the number of neutrons in the nucleus of this atom. Al Atomic Number This represents the number of protons in the nucleus of this atom. Aluminum 17 WRITE

Let’s look at the Periodic Table When looking at an Element on the Periodic Table, we can get a lot of information. 13 Al This icon tells whether the Element is a solid, a liquid or a gas at room temperature. Some periodic tables don’t have this. Aluminum 17 WRITE

There is 1 electron for every proton. Important Rule #1 There is 1 electron for every proton. Remember, the electrons are so small we don’t bother to count their weight, but they are important when it comes to charge. WRITE

To figure out how many Neutrons are in an atom… Important Rule #2 To figure out how many Neutrons are in an atom… Atomic Weight Atomic Number Number of Neutrons WRITE

Try These

He 2 4 Helium What is the atomic symbol for this element ? What is the name of this element ? What is the atomic weight of this element ? How many protons are in 1 atom of this element ? How many neutrons are in 1 atom of this element ? How many electrons are in 1 atom of this element ? What state of matter is this element in at room temperature ? 2 He Helium 4

Au 79 197 Gold What is the atomic symbol for this element ? What is the name of this element ? What is the atomic weight of this element ? How many protons are in 1 atom of this element ? How many neutrons are in 1 atom of this element ? How many electrons are in 1 atom of this element ? What state of matter is this element in at room temperature ? 79 Au Gold 197

W 74 184 Tungsten What is the atomic symbol for this element ? What is the name of this element ? What is the atomic weight of this element ? How many protons are in 1 atom of this element ? How many neutrons are in 1 atom of this element ? How many electrons are in 1 atom of this element ? What state of matter is this element in at room temperature ? 74 W Tungsten 184

Hg 80 201 Mercury What is the atomic symbol for this element ? What is the name of this element ? What is the atomic weight of this element ? How many protons are in 1 atom of this element ? How many neutrons are in 1 atom of this element ? How many electrons are in 1 atom of this element ? What state of matter is this element in at room temperature ? 80 Hg Mercury 201

Kr 36 84 Krypton What is the atomic symbol for this element ? What is the name of this element ? What is the atomic weight of this element ? How many protons are in 1 atom of this element ? How many neutrons are in 1 atom of this element ? How many electrons are in 1 atom of this element ? What state of matter is this element in at room temperature ? 36 Kr Krypton 84

Here's A Puzzle

Scandium Hydrogen Oxygen Oxygen Lithium Sulfur Fluorine Uranium Nitrogen

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