Properties of Matter
States Of Matter Solid: maintains a fixed volume and shape
Liquid: maintains a fixed volume but takes the shape of the container
Gas: occupies the entire volume available
Plasma: occurs at high temperatures
Phase Changes
Phase Change Diagram
Physical and Chemical Properties
Physical Properties:examples: texture, shape, size, color,
odor, volume, mass, weight, and density
Chemical Properties: example: color change, energy
given off or absorbed, gas given off, odor change, light, solid produced from solution
Physical and Chemical Changes
Physical Change: when objects undergo a change that does not change their chemical nature. Involves a change in physical properties
Chemical Change: substances are changed into different substances. The composition of the substance changes.
Intensive and Extensive Properties
Intensive Properties: Properties that do not depend on how much of the substance you have.
Examples: Temperature, pressure, density, boiling point, solubility, color
Extensive Properties: Depend on the amount of the substance.
Examples: Mass and volume
Density Density= Mass/Volume
Describes the degree of compactness of a substance – ( how closely packed together the atoms of an element, molecule or compound are.) Is a physical or intensive property.
Properties of an Element:Element: a pure chemical
substance composed of atoms with the same number of protons
not easily broken down into it’s smaller parts
very distinctive properties
properties are different from the compounds they make up
Gold
Mercury
Sodium
Chlorine Gas
Properties of Compounds:
COMPOUND:
has a constant composition with fixed ratios of elements
physical properties such as boiling point or melting point of pure substances constant.
Example: pure water boils at 100 °C
Table salt: NaCl
Pure Water: H2O
Carbon Dioxide: CO2
WHAT ARE MIXTURES? MIXTURE : •a combination of two or more substances that are not chemically united
• do not exist in fixed proportions
•most natural substances are mixtures
Properties of MixturesMIXTURES: can be physically
separated into pure compounds or elements.
just about everything that you can think of is probably a mixture.
may exhibit a changing set of physical properties.
Concrete
Sea Water
Vegetable soup
Heterogeneous MixtureHetero: indicates difference
consists of visibly different substances or phases
the four phases are gas, liquid, solid, and plasma
Example: beach sand, vinegar and oil salad dressing, air with clouds
Italian Salad Dressing
Jello with Fruit
Air with Clouds
Examples of heterogeneous mixtures:
"Dancing Raisins" shows liquid, solid, and gas substances in a heterogeneous mixture.
•Vinegar + Baking Soda – forms a heterogeneous solution: there are liquids and gases present.
Homogeneous MixturesHomo: indicates sameness
has the same uniform appearance and composition throughout.
are commonly referred to as solutions.
Examples: corn oil , white vinegar , sugar solution, air (with no clouds)
Kool-Aid
Swimming Pool Water
Air with no Clouds
Solutions Are distinguished by particle size.
Homogeneous solutions have particles which are the size of atoms or molecules - too small to be seen.
Homogeneous solutions are two or more substances in a single phase.
The concentrations may be expressed using a variety of measures.
Law of conservation of Matter Fundamental principle that states that
matter cannot be created or destroyed. In a chemical reaction the sum of all the
masses of the substances involved in the reaction (reactants) is equal to the sum of all of the masses of the substances produced by the reaction (products) .
No matter is gained or lost.
Percent (%) Mass The mass of the part (usually in grams) divided by
the mass of the whole (usually in grams) times 100.
mass % = mass of part / mass of whole X 100
Example: Hot Chocolate with Marshmallows mass of marshmallows: 2.5 grams mass of hot chocolate with marshmallows: 105.26 grams % Mass of Marshmallow: (2.5 g / 105.26 g) X (100) = 2.38 %
Symbols for Elements To write a symbol for an element -
you must follow these rules: 1st letter is always a capital letter. 2nd letter (if there is one) is always
lower case
Examples:Hydrogen: H Mercury: HgChlorine: Cl Lead: PbPhosphorus: P Potassium: K
Formulas for Compounds Compounds have a definite composition. The formula is very specific for that compound. If the formula changes in any way –it becomes a
different compound. Examples:
Water: H2O Hydrogen Peroxide: H2O2
Iron (II) Oxide: FeO Iron (III) Oxide: Fe2O3
Carbon Dioxide: CO2 Carbon Monoxide: CO