What is Matter?

Matter is anything that has mass and takes up space. Matter can be classified into 2 groups: Pure substance or mixture.

Classifying Matter

Pure Substance ElementCompound Mixture HomogenousHeterogenous

Classifying Matter Element a substance in which all atoms are alike Elements in nature are stable –Elements from labs are unstable - exist only for short periods of time Aluminum- can be used as a blanket because it reflects radiation (a form of heat) Compound Two or more elements joined together

Classifying Matter C S 8 H 2 O Cl 2 H 2 O 2 Element - Atom Element- Molecule Compound Compound

Classifying Matter Heterogenous made of materials that can be distinguished from each other –Not uniform in composition –Colloid-mixture with large particles that never settle –Suspension Homogeneous contains two or more gaseous, liquid, or solid substance blended evenly throughout Solution- homogeneous mixtures containing particles so small they cannot be seen with a microscope and will never settle to the bottom of the container Mixture- made up of two or more substances- can be separated by physical means

Classifying Matter Colloid vs. Solution-pass a beam of light through the mixture –If the beam is invisible- it is a solution –If the beam is visible- it is a colloid The visible beam through the colloid is called the Tyndall effect Suspension- heterogeneous mixture containing a liquid in which visible particles settle out over time – like dirty water

Physical vs. Chemical Properties

Physical Properties & Changes: Physical Property any characteristic of a material that you can observe or attempt to observe without changing the identity of the substance –For example: color, shape, size, melting point, and boiling point. Behavior of substances- magnetism, ductility- ability of metal to be drawn into wires; malleability- ability of metal to be shaped- pounded into sheets; ability to flow

Physical Properties & Change: Physical Change IDENTITY DOES NOT CHANGE –a change in size, shape, or state of matter –may or may not involve energy changes and color changes Distillation- separating a mixture through evaporating a liquid and re- condensing its vapor. –Vapors from the liquid with the lowest boiling point form first and are condensed and collected

Chemical Properties & Change: Chemical Property Chemical Property- characteristic of a substance that indicates whether it can undergo a certain chemical change

Chemical Properties & Changes: Chemical Change change in identity changes the COMPOUND or SUBSTANCE Dark bottles- block light- prevents change in identity Indications that a chemical change MAY have occurred: –Smell, heat, light, sound, color change, production of gas or precipitate Color change does not always indicate a chemical change –Example: Yellow and blue make green demo

Chemical Changes hemical/ hemical/

Physical and Chemical changes Chemical changes can be used to separate substances- done in labs- metals can be removed from ore this way Examples- –Weathering is a physical change when rocks split as water freezes or as erosion occurs –Chemical change when acidic water reacts with limestone and results in a new substance that dissolves in water and washes away.

Physical and Chemical changes Identify if the reaction is a chemical or physical change: a.Mixing baking soda and vinegar b.Breaking a cookie c.Placing a penny in vinegar d.Boiling water e.Burning paper

Law of Conservation of Mass Mass cannot be created or destroyed –Burning a log seems to make mass disappear –“missing” mass is actually present in the gases that are produced as the log burns –