Lecture Presentation Chapter Chemistry in Our Lives Karen C Timberlake General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chapter Chemistry in our Lives Forensic scientists work in crime laboratories where they analyze bodily fluids and tissue samples collected by the crime scene investigators General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc 1.1 Chemistry and Chemicals Chemists working in laboratories test new products and develop new pharmaceuticals Learning Goal Define the term chemistry and identify substances as chemicals General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc What is Chemistry? Chemistry • is the study of composition, structure, properties, and reactions of matter • happens all around you every day Antacid tablets undergo a chemical reaction when dropped in water General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chemistry and Matter Matter is another word for all substances that make up our world • Antacid tablets are matter • Water is matter • Glass is matter • Air is matter General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chemicals Chemicals are • substances that have the same composition and properties wherever found • often substances made by chemists that you use every day Toothpaste is a combination of many chemicals General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chemicals in Toothpaste General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chemicals in the Kitchen General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Study Check Which of the following contains chemicals? A Sunlight B Fruit C Milk D Breakfast cereal General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Solution Which of the following contains chemicals? A Sunlight is energy; it does not contain chemicals B Fruit is a type of matter; it contains chemicals C Milk is a type of matter; it contains chemicals D Breakfast cereal is a type of matter; it contains chemicals Only B fruit, C milk, and D breakfast cereal contain chemicals General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Interpreting Graphs In the following graph, the • volume of a gas in a balloon is plotted against its temperature • y axis represents the volume (L) of the gas in the balloon • x axis represents the temperature (°C) of the gas • title indicates that the volume of the balloon was measured at different temperatures General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Interpreting Graphs The line on the graph • indicates a direct relationship: that the volume of a gas in a balloon increases with increasing temperature • can be used to determine the gas volume at various temperatures General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc F Scientific Notation People have an average of × 105 hairs on the scalp Each hair is about × 10−6 m wide Key Math Skill Writing Numbers in Scientific Notation General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Scientific Notation Numbers written in scientific notation have two parts: Coefficient Power of 10 To write 2400 in the correct scientific notation, • the coefficient is 2.4 • the power of 10 is • write the product of the coefficient multiplied by a power of 10 2.4 × 103 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Scientific Notation 400 103 = 2.4 × 000 places 2.4 × Coefficient × Power of 10 0.00086 = places = = 8.6 × 10−4 Coefficient × Power of 10 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Some Positive Powers of 10 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Some Negative Powers of 10 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Measurements in Scientific Notation Diameter of chickenpox virus 000 m = × 10−7 m General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake = 0.000 © 2016 Pearson Education, Inc Some Measurements Written in Scientific Notation General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Scientific Notation and Calculators Numbers in scientific notation can be entered into a calculator using the EXP or EE key The calculator display shows a number between and 10 followed by a space and the power of 10 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Guide to Writing a Number in Scientific Notation General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Study Check Write each of the following in correct scientific notation: A 64 000 B 0.021 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Solution Write each of the following in correct scientific notation: A 64 000 STEP Move the decimal point to obtain a coefficient that is at least but less than 10 6.4 STEP Express the number of places moved as a power of 10 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Solution Write each of the following in correct scientific notation: B 0.021 STEP Move the decimal point to obtain a coefficient that is at least but less than 10 2.1 STEP Express the number of places moved as a power of 10 10−2 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Concept Map General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc ... General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chemicals in Toothpaste General, Organic, and Biological Chemistry: Structures. .. Hypothesis (H) General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc General, Organic, and Biological Chemistry: Structures of Life,... milk, and D breakfast cereal contain chemicals General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc General, Organic, and Biological