Chapter 1: An Introduction to Chemistry Turning on the Light © 2003 John Wiley and Sons Publishers Stone/Getty Images

How does a battery works

Figure 1.3: An electric light bulb. © 2003 John Wiley and Sons Publishers Courtesy Ken Karp

Figure 1.5: The effect of sucrose and of sodium chloride on water’s ability to conduct an electric current. © 2003 John Wiley and Sons Publishers

How does Table Salt causes Conduction of Electricity?

Figure 1.1: The electrical circuit of a flashlight. © 2003 John Wiley and Sons Publishers

Figure 1.2: The electrical conductivity of tap water, sugar water, and salt water. © 2003 John Wiley and Sons Publishers

Electrolytes  Produce positive (+) and negative (-) ions when they dissolve in water.  In water conduct an electric current. Electrolytes

Strong electrolytes ionize 100% in solution. Equations for the dissociation of strong electrolytes show the formation of ions in aqueous (aq) solutions. H 2 O 100% ions NaCl(s) Na + (aq) + Cl - (aq) Strong Electrolytes

 Nonelectrolytes  Form only molecules in water.  Do not produce ions in water.  Do not conduct an electric current. Nonelectrolytes

The Scientific Method Observation and Experiments Patterns & Trends Formulate & Tests Hypothesis Theory Laws

An element is a substance that consist of the same atoms. 115 elements have been identified 83 elements occur naturally on Earth gold, aluminum, lead, oxygen, carbon Universe:H(91%);He(8.75%);Others(0.25%) Many elements have been created by scientists technetium, americium, seaborgium 1.4

Elements mercury, copper, and carbon. © 2003 John Wiley and Sons Publishers Courtesy Ken Karp

Figure 2.3: Distribution of the elements in the universe. © 2003 John Wiley and Sons Publishers

Figure 2.4: Distribution of the elements in the human body. © 2003 John Wiley and Sons Publishers

Figure 2.5: Composition of the human body. © 2003 John Wiley and Sons Publishers

Carbon, oxygen, and hydrogen are the most abundant elements in the human body. Elements in the Body

Names of Elements WtFtEMhttp:// WtFtEM Table/abc.htmhttp:// Table/abc.htm bHGQohttp:// bHGQo

Select the correct symbol for each: A. Calcium 1) C2) Ca3) CA B. Sulfur 1) S2) Sl3) Su C. Iron 1) Ir2) FE3) Fe Learning Check

Select the correct symbol for each: A. Calcium 2) Ca B. Sulfur 1) S C. Iron 3) Fe Solution

Select the correct name for each symbol: A. N 1) neon 2) nitrogen 3) nickel B. P 1) potassium 2) phogiston3) phosphorus C. Ag 1) silver 2) agean3) gold Learning Check

Select the correct name for each: A. N 2) nitrogen B. P 3) phosphorus C. Ag 1) silver Solution

What Happens if we pass electricity through water? When was the last time you did Electrolysis?

What are Compounds? Substances composed of two or more elements in a fixed ratio. H 2 O( Water) NaCl (Table Salt), C 12 H 22 O 11 (sugar)

Compounds and Mixtures02

Sodium chloride, hydrogen peroxide, water, and sucrose are some of the more common compounds of our everyday world. © 2003 John Wiley and Sons Publishers Courtesy Ken Karp

© 2003 John Wiley and Sons Publishers What do you think would be the result of placing the wires into a solution made up of a mixture of equal parts of sucrose and sodium chloride? QUESTION

© 2003 John Wiley and Sons Publishers Would you expect to find many ions in pure water? Explain. QUESTION

© 2003 John Wiley and Sons Publishers How would you go about determining whether an aspirin tablet contains any electrolytes among its ingredients? QUESTION