Matter and Life: Fundamentals of General, Organic, and Biological Chemistry

1. Fundamentals of General, Organic, and Biological Chemistry 5th Edition Chapter One Matter and Life James Mayhugh Oklahoma City University 2007 Prentice Hall, Inc.

2. Outline • 1.1 Chemistry: The Central Science • 1.2 States of Matter • 1.3 Classification of Matter • 1.4 An Example of a Chemical Reaction • 1.5 Chemical Elements and Symbols • 1.6 Elements and the Periodic Table Chapter One

4. Chemistry:The study of the properties and transformations of matter. • Matter: Anything that has mass and occupies space – things you can see, touch, taste, or smell. • Property:A characteristic that can be used to describe a substance. Substances have both physicalproperties and chemical properties. • Transformations:A change in the properties of matter with time. There are physicalchanges and chemical changes. Chapter One

5. Substances have both physical and chemicalproperties. • Physical Properties: Density, color, and melting point are physical properties of matter. Observing a physical property can be done without altering the makeup of a substance. • Chemical Properties:Chemical composition, what matter is made of, and chemical reactivity, how matter behaves, are chemical properties. Observing a chemical property alters the substance. Chapter One

8. Physical Change:Does not alter the chemical makeup of a substance. • Chemical reactivity is unchanged. • Changes in state, changes in particle size, and the formation / separation of mixtures are all examples of physical change. • Melting of ice to form liquid water is a physical change. In this case only a change in form takes place. The chemical makeup of the substance remains H2O. Chapter One

9. Chemical Change: Alters the makeup of a substance. • Reactivity changes with the formation of new substances. • Heat, light, or electrical energy is often emitted or absorbed. • Potassium reacting with water is an example of a chemical change. Chapter One

10. Intensive and Extensive Properties • Intensive Properties • Properties are the same regardless of size or amount of material. • Examples: density, color, melting point, conductivity • Extensive Properties • Properties are dependent on size and amount of material. • Examples: mass, length, volume, shape, texture Chapter One

11. 1.2 States of Matter • Common states of matter are: solid, liquid, and gas. • Solid:A substance that has a definite shape and volume. Solids are rigid and dense. • Liquid: A substance that has a definite volume but that changes shape to fill the container. Liquids are dense and fluid. Chapter One

12. Common states of matter are: solid, liquid, and gas. • Gas: A substance that has neither a definite volume nor a definite shape. Gases are low density fluids. • Substances can exist in each of these three states depending on the pressure and the temperature. The conversion of a substance from one state into another is known as change of state. Chapter One

13. The three states - the solid state, the liquid state, and the gaseous state - of water are shown below. Chapter One

14. 1.3 Classification of Matter • Pure Substance: Matter that is uniform in its chemical composition and properties. Sugar is a pure substance and water is a pure substance. • Mixture: A blend of two or more pure substances in any ratio, each retaining their identity. Dissolving sugar in water creates a mixture. • Physical changes can separate mixtures into one or more pure substances. Evaporation and condensation can separate water from sugar. Chapter One

15. Element: Pure substance that cannot be broken down chemically into simpler substances. Hydrogen and oxygen are examples of elements. • Chemical Compounds: Two or more elements combined chemically in specific ratios to form a pure substance. Water is a compound composed of two parts hydrogen and one part oxygen. • Chemical changes can separate chemical compounds into elements. Water can be broken down into hydrogen and oxygen by passing an electric current through it. Chapter One

16. The classification of matter is summarized below. Chapter One

18. 1.4 Example of a Chemical Reaction • Nickel, a solid metal, is mixed with a colorless solution of hydrochloric acid in a test tube. • The nickel is slowly eaten away, the colorless solution turns green, and a colorless gas bubbles out of the test tube. Chapter One

19. Nickel + Hydrochloric Acid Chapter One

20. Nickel + Hydrochloric Acid Chapter One

22. Reactants:One or more starting materials. Between reactants, the “+” can be read as “reacts with.” • Products: One or more substances formed as a result of a chemical reaction. Between products, the “+” can be read as “and.” • Between products and reactants, the “” can be read as “to yield” or “to form.” Chapter One

23. 1.5 Chemical Elements and Symbols • 114 elements have been discovered. • 90 occur naturally. • 24 are produced artificially. • Some familiar elements are iron, tin, carbon, oxygen, hydrogen, sulfur, etc. • Some unfamiliar elements are niobium, rhodium, thulium, californium, etc. Chapter One

25. Each element has its own unique symbol. One or two letter symbols are used to represent elements. The first letter is always capitalized and the second letter is always a lowercase. Examples: C, Cr, P, Pb • Most symbols are derived from modern names and are easy to remember. Examples: “H” for hydrogen, “O” for oxygen, “N” for nitrogen, etc. • Be careful when writing symbols: “Co” is cobalt (an element), whereas “CO” is carbon monoxide (a compound). Chapter One

26. A few symbols for elements are derived from their Latin names and are more difficult to learn. Examples: “Na” for sodium comes from its Latin name Natrium, “Pb” for lead comes from its Latin name Plumbum. • All naturally occurring elements are not equally abundant. Oxygen and silicon together constitute 75% of the Earth’s crust. Chapter One

27. Chemical Formula: A notation for a chemical compound using symbols and subscripts to show how many atoms of each element are present. When no subscript is given for an element a subscript of “1” is understood. Chapter One

29. Large amounts of information regarding the properties of elements are embedded in the periodic table. Elements are roughly divided into 3 groups: • Metals: Found on the left side of the table. • Nonmetals: Found on the right side of the table. • Metalloids: Found along a diagonal line between metals and nonmetals. Chapter One

30. A metal (red), a nonmetal (blue), and a metalloid (green) appear in distinct places on the periodic table Chapter One

31. Metals: 90 of the 114 elements are metals. They appear on the left side of the periodic table. • Some common properties of metals are: • Solid at room temperature (except mercury which is a liquid) • Good conductor of heat and electricity • Lustrous on fresh surfaces • Malleable and ductile Chapter One

32. Metals: (a) Gold is very unreactive and is used primarily in jewelry and in electronic components. • (b) Zinc, an essential nutrient, is used in the manufacture of brass, roofing materials, and batteries. • (c) Copper is widely used in electrical wiring, in water pipes, and in coins. Chapter One

33. Nonmetals: Appear on the right side of the periodic table. 17elements are nonmetals. • Elevenare gases at room temperature (H, N, O, F, Ne, etc.). • Five are solids (C, P, S, Se, I). • One is a liquid (Br). • Nonmetals are poor conductors of heat and electricity. Chapter One

34. Nonmetals:(a) Nitrogen constitutes almost 80% of air and is a colorless gas at room temperature. • (b) Sulfur, a yellow solid, is found in large underground deposits in Texas and Louisiana. • (c) Iodine crystals. Chapter One

35. Metalloids: Seven elements are metalloids. Their properties are between those of metals and nonmetals. Metalloids are semiconductors and are important to the electronics industry. (a) Boron and (b) silicon are examples of metalloids. Chapter One

36. Chapter Summary • Matter is anything with mass that occupies volume. • Matter can be classified as solid, liquid, or gas. • A solid has a definite volume and shape, a liquid has a definite volume but indefinite shape, and a gas has neither a definite volume nor shape. • A substance can be characterized as being either pure or a mixture. • A pure substance is uniform in its composition and properties, but a mixture can vary in both composition and properties. Chapter One

37. Chapter Summary Cont. • Pure substances are either elements or chemical compounds. • Elements are fundamental substances that cannot be chemically changed into anything simpler. • A chemical compound can be broken down by chemical change into simpler substances. • A property describes or identifies something. • A physical property can be seen or measured without changing the chemical identity of the substance. Chapter One

38. Chapter Summary Cont. • A chemical property can only be seen or measured when the substance undergoes a chemical change. • Elements are represented by symbols. Most symbols are the first one or two letters of the element name. • Some symbols are derived from Latin names. • All the known elements are organized into a tabular form called the periodic table. • Most elements are metals, 17 are nonmetals, and 7 are metalloids. Chapter One