Classification of Matter
Classification of Matter Chapter 15
Classification of Matter
Classification systems are used to organize. – e.g.
Grocery stores—frozen foods, dairy, meat Libraries—Use Dewey Decimal system Science—To make studying matter easier
Matter
Solutions
Elements Mixtures Compounds When classifying matter, our job is to figure out the way nature is, not to tell nature how to behave.
Mixtures:
Two or more substances mixed together but not chemically combined.
Mixtures:
Properties of Mixtures: 1. Each combined substance retain their separate identities. e.g.
Salt water or salt tastes salty.
2. Substances are physically combined. 3. Substances can be physically separated. e.g.
Distilling salt water will vaporize the water off leaving the salt. - Separating a mixture of iron filings from sand with a magnet.
Mixtures: 4. Substances in a mixture can be present in varying amounts. – Pizza, Granite, Chicken noodle soup.
5. No chemical reactions are involved. 6. Can be broken down into simpler substances.
Types of Mixtures:
Heterogeneous: Matter that has parts w/different properties; least mixed e.g. Soil: May contain any combination of sand, silt, clay or organic material. Granite: Contains feldspar, mica, & quartz in varying amounts. Concrete: Contains sand, rock and cement.
Mixtures: Homogeneous: Matter w/identical properties throughout; well mixed e.g. Salt water—NaCl • H2O Sugar Water—C12H22O11 • H2O
Solutions:
Solutions are a special type of homogeneous mixture formed when one substance dissolves in another.
Can be solids, liquids, or gases. e.g. Brass: Copper and Zinc Seawater: H2O + NaCl + Mg + Ca + CO2
Properties of Solutions:
Unique Properties of Solutions– 1. 2. 3. 4. 5.
Particles in solution are invisible. Particles in solution are evenly spaced. Substance that is dissolved is the solute. Substance doing the dissolving is the solvent. A solution of metals is an alloy. -Brass
+ Copper
= Zinc
Brass
Pure Substances
Matter made of one kind of material and has definite chemical properties.
Pure substances cannot be separated by physical means. E.g. carbon, methane, water, etc.
Types of Pure Substances
Elements: Substances containing one or more identical atoms. – An atom is the smallest part of an element
that still has the properties of that element. – Elements are the simplest pure substances.
Types of Pure Substances
Molecules are substances made of two or more atoms chemically combined (covalently bonded).
Smallest particle of a compound that has all the properties of that compound.
All molecules of a compound are alike. e.g. Water; molecules of H2O
Types of Pure Substances
Compounds are two or more elements chemically combined. – Pure, homogeneous substance. – Compounds are made of molecules. – Unlike mixtures, compounds must be separated chemically. – Examples of Compounds: H2O, NH3, CO2, C6H12O6, NaCl
Chemical Symbols:
Shorthand way of representing the chemical elements. – Usually the first letter of the element. – e.g. C=Carbon O=Oxygen H=Hydrogen
Chemical Symbols:
If the first letter is already used, another letter in the element’s name follows the first letter. – e.g.
Si=Silicon Cl= Chlorine Cr=Chromium
Chemical Symbols:
Sometimes the first two letters of an elements Latin meaning is used: – e.g.
Fe=Ferrum=Iron Au=Aurum=Gold Ag=Argentum=Silver Hg=Hydragyrum=Mercury
Chemicals Formulas:
Chemical formulas are a combination of chemical symbols that represent compounds (or molecules) – NH3 = Ammonia
1 Nitrogen and 3 Hydrogen
– O2 = Diatomic Oxygen 2 Oxygen Atoms
– 7 Diatomic Molecules: Cannot stand alone—Must be in a pair. Br2, O2, Cl2, I2, F2, N2, H2
Chemical Equations:
Chemical equations are descriptions of chemical reactions using symbols and formulas – i.e. A chemical sentence.
e.g.
C atoms of C
+
O2 molecule of O
CO2 Molecule of Carbon Dioxide
Chemical Equations: e.g.
H2 molecule of H
+
O2 molecule of O
H2O
Water molecule
Q: What’s wrong with the above equation? A: It’s not balanced.
2H2
+
O2
2H2O subscript denotes 2 atoms of O coefficient denotes 2 H2 molecules
Chemical Equations:
A chemical change can be described using symbols and formulas that show the reaction which is known as a chemical equation.
Classification of Matter
Classification systems are used to organize. – e.g.
Grocery stores—frozen foods, dairy, meat Libraries—Use Dewey Decimal system Science—To make studying matter easier
Matter
Solutions
Elements Mixtures Compounds When classifying matter, our job is to figure out the way nature is, not to tell nature how to behave.
Mixtures:
Two or more substances mixed together but not chemically combined.
Mixtures:
Properties of Mixtures: 1. Each combined substance retain their separate identities. e.g.
Salt water or salt tastes salty.
2. Substances are physically combined. 3. Substances can be physically separated. e.g.
Distilling salt water will vaporize the water off leaving the salt. - Separating a mixture of iron filings from sand with a magnet.
Mixtures: 4. Substances in a mixture can be present in varying amounts. – Pizza, Granite, Chicken noodle soup.
5. No chemical reactions are involved. 6. Can be broken down into simpler substances.
Types of Mixtures:
Heterogeneous: Matter that has parts w/different properties; least mixed e.g. Soil: May contain any combination of sand, silt, clay or organic material. Granite: Contains feldspar, mica, & quartz in varying amounts. Concrete: Contains sand, rock and cement.
Mixtures: Homogeneous: Matter w/identical properties throughout; well mixed e.g. Salt water—NaCl • H2O Sugar Water—C12H22O11 • H2O
Solutions:
Solutions are a special type of homogeneous mixture formed when one substance dissolves in another.
Can be solids, liquids, or gases. e.g. Brass: Copper and Zinc Seawater: H2O + NaCl + Mg + Ca + CO2
Properties of Solutions:
Unique Properties of Solutions– 1. 2. 3. 4. 5.
Particles in solution are invisible. Particles in solution are evenly spaced. Substance that is dissolved is the solute. Substance doing the dissolving is the solvent. A solution of metals is an alloy. -Brass
+ Copper
= Zinc
Brass
Pure Substances
Matter made of one kind of material and has definite chemical properties.
Pure substances cannot be separated by physical means. E.g. carbon, methane, water, etc.
Types of Pure Substances
Elements: Substances containing one or more identical atoms. – An atom is the smallest part of an element
that still has the properties of that element. – Elements are the simplest pure substances.
Types of Pure Substances
Molecules are substances made of two or more atoms chemically combined (covalently bonded).
Smallest particle of a compound that has all the properties of that compound.
All molecules of a compound are alike. e.g. Water; molecules of H2O
Types of Pure Substances
Compounds are two or more elements chemically combined. – Pure, homogeneous substance. – Compounds are made of molecules. – Unlike mixtures, compounds must be separated chemically. – Examples of Compounds: H2O, NH3, CO2, C6H12O6, NaCl
Chemical Symbols:
Shorthand way of representing the chemical elements. – Usually the first letter of the element. – e.g. C=Carbon O=Oxygen H=Hydrogen
Chemical Symbols:
If the first letter is already used, another letter in the element’s name follows the first letter. – e.g.
Si=Silicon Cl= Chlorine Cr=Chromium
Chemical Symbols:
Sometimes the first two letters of an elements Latin meaning is used: – e.g.
Fe=Ferrum=Iron Au=Aurum=Gold Ag=Argentum=Silver Hg=Hydragyrum=Mercury
Chemicals Formulas:
Chemical formulas are a combination of chemical symbols that represent compounds (or molecules) – NH3 = Ammonia
1 Nitrogen and 3 Hydrogen
– O2 = Diatomic Oxygen 2 Oxygen Atoms
– 7 Diatomic Molecules: Cannot stand alone—Must be in a pair. Br2, O2, Cl2, I2, F2, N2, H2
Chemical Equations:
Chemical equations are descriptions of chemical reactions using symbols and formulas – i.e. A chemical sentence.
e.g.
C atoms of C
+
O2 molecule of O
CO2 Molecule of Carbon Dioxide
Chemical Equations: e.g.
H2 molecule of H
+
O2 molecule of O
H2O
Water molecule
Q: What’s wrong with the above equation? A: It’s not balanced.
2H2
+
O2
2H2O subscript denotes 2 atoms of O coefficient denotes 2 H2 molecules
Chemical Equations:
A chemical change can be described using symbols and formulas that show the reaction which is known as a chemical equation.
