Presentation on theme: "Chemistry Matter and Change. Chemistry is… …the study of the composition, structure, and properties of matter and the changes it undergoes C 2 H 5 OH."— Presentation transcript:
Chemistry Matter and Change
Chemistry is… …the study of the composition, structure, and properties of matter and the changes it undergoes C 2 H 5 OH + 3 O 2 2 CO H 2 O + Energy Reactants Products
Matter Anything that has mass and occupies space Mass A measure of the amount of matter
Atom The smallest unit of an element that maintains the properties of that element Element A pure substance made of only one kind of atom
Compound A substance that is made from the atoms of two or more elements that are chemically bonded. Sucrose – C 12 H 22 O 11 Sucrose is also known as table sugar, and is used to make Gummy Bears!
Properties of Matter Extensive properties Intensive properties Volume Mass Energy Content (think Calories!) depend on the amount of matter that is present. do not depend on the amount of matter present. Melting point Boiling point Density
Physical Change A change in a substance that does not involve a change in the identity of the substance. Example: Phase Changes
Phase Differences Solid Solid – definite volume and shape; particles packed in fixed positions. Liquid Liquid – definite volume but indefinite shape; particles close together but not in fixed positions Gas Gas – neither definite volume nor definite shape; particles are at great distances from one another Plasma – high temperature, ionized phase of matter as found on the sun.
Copper Phases - Solid
Copper Phases - Liquid
Copper Phases – Vapor (gas)
Chemical Change A change in which one or more substances are converted into different substances. Heat and light are often evidence of a chemical change.
Classification of Matter
Separation of a Mixture The constituents of the mixture retain their identity and may be separated by physical means.
Separation of a Mixture The components of dyes such as ink may be separated by paper chromatography.
Separation of a Mixture Distillation
Separation of a Compound Separation of a Compound The Electrolysis of water Water Hydrogen + Oxygen H 2 O H 2 + O 2 Reactant Products Compounds must be separated by chemical means. With the application of electricity, water can be separated into its elements
The Periodic Table Period Group or family Period Group or Family
Properties of Metals Metals are good conductors of heat and electricity Metals are malleable Metals are ductile Metals have high tensile strength Metals have luster
Examples of Metals Potassium, K reacts with water and must be stored in kerosene Zinc, Zn, is more stable than potassium Copper, Cu, is a relatively soft metal, and a very good electrical conductor. Mercury, Hg, is the only metal that exists as a liquid at room temperature
Propertiesof Nonmetals Properties of Nonmetals Carbon, the graphite in pencil lead is a great example of a nonmetallic element. Nonmetals are poor conductors of heat and electricity Nonmetals tend to be brittle Many nonmetals are gases at room temperature
Examples of Nonmetals Sulfur, S, was once known as brimstone Microspheres of phosphorus, P, a reactive nonmetal Graphite is not the only pure form of carbon, C. Diamond is also carbon; the color comes from impurities caught within the crystal structure
Properties of Metalloids Metalloids straddle the border between metals and nonmetals on the periodic table. They have properties of both metals and nonmetals. Metalloids are more brittle than metals, less brittle than most nonmetallic solids Metalloids are semiconductors of electricity Some metalloids possess metallic luster
Silicon, Si – A Metalloid Silicon has metallic luster Silicon is brittle like a nonmetal Silicon is a semiconductor of electricity Other metalloids include: Boron, B Germanium, Ge Arsenic, As Antimony, Sb Tellurium, Te