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7-5 The Chemical Nature of Matter
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Matter Anything that has mass and takes up space (volume)
Examples of matter: Wood, paper, air, water, hair, skin, plastic, dust, gold, etc.
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So, what isn’t matter???? Light Sound
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Atoms Atoms are the basic building blocks of matter that make up everyday objects. A desk, the air, even you are made up of atoms!
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How small are atoms? Atoms are too small in size to study easily
Atoms are so small that if you lined 50,000,000 (50 million) of them up in a row, they would reach about a centimeter Size of Earth : soda can = soda can : atom
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An element is a substance made up of only 1 type of atom.
There are 90 naturally occurring kinds of atoms. Scientists in labs have been able to make about 25 more. So, there are about 115 different atom types therefore there are 115 elements.
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How can matter be classified (or organized)?
Matter can be classified as either a mixture or a pure substance. We are going to focus on this side of the chart first!
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helium carbon nitrogen sodium silver oxygen mercury neodymium chlorine
gold mercury oxygen hydrogen helium sodium niobium neodymium carbon
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CHEMICAL ELEMENTS - Aluminum Bromine Sodium
pure substances that cannot be decomposed by ordinary means to other substances. Aluminum Bromine Sodium
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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.
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Elements The elements, alone or in combinations, make up our bodies, our world, our sun, and in fact, the entire universe.
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The most abundant element in the earth’s crust is oxygen.
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The elements of aluminum, Iron, Oxygen, and Silicon make up about 88 percent of the earth's solid surface. Water on the surface and in the air as clouds and fog is made up of hydrogen and oxygen. The air is 99 percent nitrogen and oxygen. Hydrogen, oxygen, and carbon make up 97 percent of a person. Thus almost everything you see in this picture us made up of just six elements.
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ELEMENT NOTES Elements
· Elements are pure substances that cannot be changed into simpler substances. · Elements are composed of one kind of atom. You will need to know: Na = O = Cl = C = H = N =
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Periodic Table of Elements
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Periodic Table The periodic table organizes the elements in a particular way. A great deal of information about an element can be gathered from its position in the period table. For example, you can predict with reasonably good accuracy the physical and chemical properties of the element. You can also predict what other elements a particular element will react with chemically. Understanding the organization and plan of the periodic table will help you obtain basic information about each of the 118 known elements.
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Key to the Periodic Table
Elements are organized on the table according to their atomic number, usually found near the top of the square. The atomic number is unique to that element. No two elements have the same atomic number.
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Every table has:
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Atomic Symbol: The atomic symbol is one or two letters chosen to represent an element ("H" for "hydrogen," etc.). These symbols are used every where in the world Usually, a symbol is the abbreviation of the element or the abbreviated Latin name of the element.
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C Cu Symbols Carbon Copper All elements have their own unique symbol.
It can consist of a single capital letter, or a capital letter and one or two lower case letters. C Carbon Cu Copper
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Common Elements and Symbols
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Glenn Seaborg (1912-1999 ) Discovered 8 new elements.
Only living person for whom an element was named.
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Click the link below for an amazing pictorial periodic table.
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Periods and Groups Horizontal rows in the periodic table are called periods Vertical columns are called groups
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Families Periods Columns of elements are called groups or families.
Elements in each family have similar but not identical properties. For example, lithium (Li), sodium (Na), potassium (K), and other members of Group 1 are all soft, white, shiny metals. Each horizontal row of elements is called a period. The elements in a period are not alike in properties. In fact, the properties change greatly across even given row. The first element in a period is always an extremely active solid. The last element in a period, is always an inactive gas.
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These symbols are used every where in the world
ATOMIC SYMBOL The atomic symbol is one or two letters chosen to represent an element ("H" for "hydrogen," etc.). These symbols are used every where in the world Usually, a symbol is the abbreviation of the element or the abbreviated Latin name of the element.
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· A horizontal row on the periodic table is called a period.
· Every periodic table will have a square for each element with the atomic number, atomic mass, element name, and the element symbol. · The elements on the periodic table are arranged numerically by atomic numbers. · Families, also called groups, are vertical columns of elements on the periodic table; they are usually numbered Elements in the same family have similar properties.
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Metals · A major classification of elements generally located on the left side of the zigzag line on the periodic table. · Examples of metals are: Sodium (Na), Calcium (Ca), Iron (Fe), and Aluminum (Al). The majority of elements are metals. Nonmetals · A major classification of elements generally located on the right side of the zigzag line on the periodic table. · Examples of nonmetals are: Chlorine (Cl), Oxygen (O), Sulfur (S), and Iodine (I).
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Periodic Table: Metallic arrangement
Layout of the Periodic Table: Metals vs. nonmetals Nonmetals Metals
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Properties of Metals Metals are good conductors of heat and electricity. Metals are lustrous (shiny). Metals are ductile (can be stretched into thin wires). Metals are malleable (can be pounded into thin sheets). Metals have high density (they are heavy for their size) A chemical property of metal is its reaction with water which results in corrosion.
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Properties of Non-Metals
Non-metals are poor conductors of heat and electricity. Non-metals are not ductile or malleable. Solid non-metals are brittle and break easily. They are dull. Many non-metals are gases. Sulfur
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Properties of Metalloids
Metalloids (metal-like) have properties of both metals and non-metals. They are solids that can be shiny or dull. They conduct heat and electricity better than non-metals but not as well as metals. They are ductile and malleable. Silicon
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How can matter be classified (or organized)?
Matter can be classified as either a mixture or a pure substance. We’ve looked at elements, now let’s look at compounds.
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Elements vs. Compounds Sodium is an element. Chlorine is an element.
When sodium and chlorine bond they make the compound sodium chloride, commonly known as table salt. Compounds have different properties than the elements that make them up. Table salt has different properties than sodium, an explosive metal, and chlorine, a poisonous gas.
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Elements vs. Compounds Hydrogen is an element. Oxygen is an element.
When hydrogen and oxygen bond they make the compound water.
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Compounds Pure substances made of two or more types of elements that are CHEMICALLY combined! Compounds can only be broken down into simpler substances or elements by CHEMICAL CHANGES!
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Chemical Formulas The formulas of compounds have more than one type of symbol showing the different elements that compose the compound. H2O This is the formula for water. Water is composed of the elements Hydrogen and Oxygen This number is called a subscript. It tells how many of each kind of atom are in the compound. There are 2 Hydrogen atoms in a molecule of water Since there is no subscript for oxygen it is assumed to be one atom of oxygen
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Other common compounds:
NaCl Table salt CO2 Carbon dioxide C6H12O6 Sugar
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Elements, compounds, and mixtures
Mixtures can be separated by physical means. Compounds can only be separated by chemical means. Elements are pure substances. When the subatomic particles of an element are separated from its atom, it no longer retains the properties of that element.
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Matter All matter is composed of atoms and groups of atoms bonded together, called molecules. Substances that are made from one type of atom only are called pure substances. Substances that are made from more than one type of atom bonded together are called compounds. Compounds that are combined physically, but not chemically, are called mixtures.
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The ocean is a mixture of salt and water.
When salt and water are combined, a mixture is created. Compounds in mixtures retain their individual properties. The ocean is a mixture of salt and water.
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