course syllabus on my web page Honors Chemistry course syllabus on my web page

Chapter 1 Matter and Change

Chapter 1 Homework Read Chapter 1

Chemistry – the study of matter and the changes that matter undergoes.

What is Matter? Matter is anything that takes up space (volume) and has mass. Mass is the amount of matter in an object. Usually measured with a balance. Volume is the amount of three dimensional space an object occupies.

Building Blocks of Matter The fundamental building blocks of matter are atoms. Element – a pure substance made of only one kind of atom. Atoms – the smallest unit of an element that maintains the properties of the element.

Element Examples – carbon, hydrogen and oxygen. The periodic table lists all the elements. Elements contain only one kind of atom.

Compound – a substance that is made from the atoms of two or more elements that are chemically bonded. Compound Examples – water (made of hydrogen and oxygen), methane (made of carbon and hydrogen) and sugar (made from carbon, hydrogen and oxygen). H2O, CH4 and CxHxOx

States of Matter The three common states of Matter: Solid Liquid Gas

Solid State – matter in the solid state has definite volume and shape. The particles that make up the solid are packed close together in relatively fixed positions. The particles are held close together by strong attractive forces.

Liquid State – matter in the liquid state has definite volume but an indefinite shape. A liquid assumes the shape of its container. The particles that make up the liquid are packed close together but can move past one another. The rapidly moving particles cause them to temporarily overcome the attractive forces between them, allowing the liquid to flow.

Gas State – matter in the gas state has no definite volume nor shape. Gases have this characteristic because they are composed of particles that move very rapidly and are at great distances from one another. A gas will expand to fill any size container and take the shape of that container.

Condense Freeze Melt Evaporate Solid Liquid Gas

Types of Matter All matter can be classified into one of two groups: pure substances or mixtures. Pure Substance – can be an element or compound. The composition of a pure substance is the same throughout and does not vary from sample to sample. Examples include: water, sugar, gold and aluminum.

Mixture – contains more than one substance. They can vary in composition and properties from sample to sample. Examples include: sugar dissolved into water, granite, brass (copper and zinc), chocolate chip cookie and air.

Mixtures Homogeneous- same composition throughout. Homogenous mixtures are also called solutions. Example: salt water solution and air Heterogeneous- mixture is not the same throughout the sample. Example: sand and water. The heavier sand settles to the bottom.

Solutions Homogeneous mixture Can occur between any state of matter. Solid in liquid- Kool-aid Liquid in liquid- antifreeze in a car radiator Gas in gas- air (oxygen, nitrogen and argon) Solid in solid – brass (copper and zinc)

Separating mixtures Only a physical change- no new matter Filtration - separate solids from liquids with a barrier (filter paper) Distillation - separate liquids because of different boiling points Heat mixture Catch vapor in cooled area

Filtration

Summary

Homework Page 26: Questions: 5, 6,12 (a-c) and 13

Chapter 1 Section 3 Elements and the Periodic Table

Element – a pure substance made of only one kind of atom. Element – pure substance that cannot be decomposed by chemical changes. Elements serve as the building block of matter. Each element has characteristic properties.

Periodic Table Elements – are organized into groups based on similar chemical properties. Periodic Table – The organization of elements is the periodic table. Each box on the periodic table lists one element and the letter symbol.

Chemical Symbols There are 118 elements Each has a 1 or two letter symbol First letter always capitalized second never Don’t need to memorize Some from Latin or other languages

Chemical Symbols Used to write chemical formulas Subscripts tell us how many of each atom H2O C3H8 H2CO3

Periodic Table Groups or Families – the vertical columns of the periodic table. The groups are number 1 to 18 from left to right. Each group contains elements with similar chemical properties.

Periodic Table Periods – the horizontal rows of elements in the periodic table. Physical and chemical properties change across a period. Elements on opposite sides of the periodic table in the same row are much different. Example is lithium and fluorine in Period 2.

Types of Elements The periodic table is broadly divided into two main sections: metals and nonmetals. The metals are at the left and the center of the table. The nonmetals are toward the right.

Metals Metal – an element that is a good conductor of heat and electricity. Properties: solids (mercury), shines, malleable (hammered), ductile (drawn into thin wires), resistance to breaking, conductors of heat and electricity.

Nonmetals Nonmetal – an element that is a poor conductor of heat and electricity. Properties: Gases – nitrogen, oxygen, fluorine and chlorine. Liquids – bromine Solids – carbon, phosphorus, sulfur, iodine

Nonmetals Properties: The solids tend to be brittle rather than malleable or ductile. Low conductors of heat and electricity.

Metalloids Metalloids – an element that has some characteristics of metals and nonmetals. A stair-step line separates the metals from the nonmetals on the periodic table.

Metalloids Properties: All metalloids are solids at room temperature. Less malleable than metals but not as brittle as nonmetals. Metalloids tend to be semiconductors of electricity. (intermediate between metals and nonmetals).

Metalloids Properties: Metalloids are used in semiconducting materials found in computers, calculators, televisions and radios. Elements include: boron, silicon, germanium, antimony

Homework Page 26: Questions: 14, 15, 17, 18, 19, 20 and 23

End of Chapter 1