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Classification of Matter Chapter 3. Larry Emme Chemeketa Community College. Matter Defined. Matter is anything that has mass and occupies space. Matter can be invisible. Matter appears to be continuous and unbroken. Physical States of Matter.
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Classification of Matter Chapter 3 Larry Emme Chemeketa Community College
Matter is anything that has mass and occupies space. • Matter can be invisible. • Matter appears to be continuous and unbroken.
Matter refers to all of the materials that make up the universe.
Substance A particular kind of matter that has a fixed composition and distinct properties. Examples ammonia, water, and oxygen.
Homogeneous Matter Matter that is uniform in appearance and with uniform properties throughout. Examples ice, soda, solid gold
Heterogeneous Matter Matter with two or more physically distinct phases present. Examples wood, blood
Phase A homogenous part of a system separated from other parts by physical boundaries. Examples In an ice water mixture ice is the solid phase and water is the liquid phase
Mixture Matter containing 2 or more substances that are present in variable amounts. Mixtures are variable in composition. They can be homogeneous or heterogeneous.
Homogeneous Mixture (Solution) A homogeneous mixture of 2 or more substances. It has one phase. Example Sugar and water. Before the sugar and water are mixed each is a separate phase. After mixing the sugar is evenly dispersed throughout the volume of the water.
Heterogeneous Mixture A heterogeneous mixture consists of 2 or more phases. Example Sugar and fine white sand. The amount of sugar relative to sand can be varied. The sugar and sand each retain their own properties.
Classification of matter: A pure substance is always homogeneous in composition, whereas a mixture always contains two or more substances and may be either homogeneous or heterogeneous.
An element is a fundamental or elementary substance that cannot be broken down into simpler substances by chemical means
All known substances on Earth and probably the universe are formed by combinations of more than 100 elements. • Each element has a number. • Beginning with hydrogen as 1 the elements are numbered in order of increasing complexity.
Most substances can be decomposed into two or more simpler substances. • Water can be decomposed into hydrogen and oxygen. • Table salt can be decomposed into sodium and chlorine. • An element cannot be decomposed into a simpler substance.
ATOM • The smallest particle of an element that can exist. • The smallest unit of an element that can enter into a chemical reaction.
Oxygen is the most abundant element in the human body (65%). • Oxygen is the most abundant element in the crust of the earth (49.2%).. • In the universe the most abundant element is hydrogen (91%) and the second most abundant element is helium (8.75%). • Elements are not distributed equally by nature.
Sources of Element Names Greek-Color • Iodine: from the Greek iodes meaning violet. Latin- Property • Fluorine: from the Latin fluere meaning to flow. German- Color • Bismuth: from the German weisse mass meaning white mass. Location • Germanium: discovered in 1866 by a German chemist. Famous- Scientist • Einsteinium: named for Albert Einstein.
A symbol stands for • the element itself • one atom of the element • a particular quantity of the element
Rules governing symbols of the elements are: • Symbols have either one or two letters. • If one letter is used it is capitalized. H hydrogen C carbon • If two letters are used, only the first is capitalized. Ne neon Ba barium
Metals are solid at room temperature. • Mercury is an exception. At room temperature it is a liquid. • Metals are good conductors of heat and electricity. Most elements are metals physical properties of metals • Metals are malleable (they can be rolled or hammered into sheets). • Metals have high luster (they are shiny).
Metals are ductile (they can be drawn into wires). • Most metals have a high melting point. • Metals have high densities
Physical Properties of Nonmetals • Lack luster (they are dull) • Have relatively low melting points • Have low densities. • Poor conductors of heat and electricity • At room temperature carbon, phosphorous, sulfur, selenium, and iodine are solids.
Metalloids have properties that are intermediate between metals and nonmetals
The Metalloids • boron • silicon • germanium • arsenic • antimony • tellurium • polonium
Metals are found to the left of the metalloids Nonmetals are found to the right of the metalloids.
A compound is a distinct substance that contains two or more elements combined in a definite proportion by weight.
A molecule is the smallest uncharged individual unit of a compound formed by the union of two or more atoms.
A water molecule consists of two hydrogen atoms and one oxygen atom. • If it is subdivided the water molecule will be destroyed and hydrogen and oxygen will be formed.
An ion is a positively or negatively charged atom or group of atoms.