1. Chapter 2 Lecture Basic Chemistry Fourth Edition Chapter 2 Measurements 2.1 Units of Measurement Learning Goal Write the names and abbreviations for the metric or SI units used in measurements of length, volume, mass, temperature, and time. © 2014 Pearson Education, Inc.

2. Key Math Skills Identifying Place Values (1.4A) © 2014 Pearson Education, Inc. Chapter 2 Readiness

3. © 2014 Pearson Education, Inc. Chemists use the metric system and the International System of Units (SI) for measurement when they measure quantities do experiments solve problems The International System of Units (SI)

4. © 2014 Pearson Education, Inc. Units of Measurement and Their Abbreviations

5. © 2014 Pearson Education, Inc. Length is measured in units of meters (m) in both the metric and SI systems units of centimeters (cm) by chemists Length

6. © 2014 Pearson Education, Inc. Useful relationships between units of length include: 1 m = 1.094 yd 1 m = 39.37 in. 1 m = 100 cm 2.54 cm = 1 in. Length

7. © 2014 Pearson Education, Inc. Volume, the space occupied by a substance, is measured using units of m 3 in the SI system is commonly measured in liters (L) and milliliters (mL) by chemists Volume

8. © 2014 Pearson Education, Inc. Useful relationships between units of volume include: 1 m 3 = 1000 L 1 L = 1000 mL 1 mL = 1 cm 3 1 L = 1.057 qt 946.3 mL= 1 qt Volume

9. © 2014 Pearson Education, Inc. The mass of an object, a measure of the quantity of material it contains, is measured on an electronic balance has the SI unit of kilogram (kg) is often measured by chemists in grams (g) Mass

10. © 2014 Pearson Education, Inc. Useful relationships between units of mass include: 1 kg = 1000 g 1 kg = 2.205 lb 453.6 g = 1 lb Mass

11. © 2014 Pearson Education, Inc. Temperature, a measure of how hot or cold an object feels, is measured on the Celsius (ºC) scale is measured on the Kelvin (K) scale in the SI system is 18 ºC or 64 ºF on this thermometer Temperature

12. © 2014 Pearson Education, Inc. Time is based on an atomic clock and is measured in units of seconds (s) in both the metric and SI systems. Time

13. © 2014 Pearson Education, Inc. For each of the following, indicate whether the unit describes (1) length, (2) mass, or (3) volume A. A bag of onions has a mass of 2.6 kg. B. A person is 2.0 m tall. C. A medication contains 0.50 g of aspirin. D. A bottle contains 1.5 L of water. Learning Check

14. © 2014 Pearson Education, Inc. For each of the following, indicate whether the unit describes (1) length, (2) mass, or (3) volume A. A bag of onions has a mass of 2.6 kg. (2) B. A person is 2.0 m tall. (1) C. A medication contains 0.50 g of aspirin. (2) D. A bottle contains 1.5 L of water. (3) Solution

15. © 2014 Pearson Education, Inc. Identify the measurement that has an SI unit. A.John’s height is _____. (1) 1.5 yd(2) 6 ft(3) 2.1 m B.The mass of a lemon is _____. (1) 12 oz(2) 0.145 kg(3) 0.6 lb C. The temperature is _____. (1) 85 ºC(2) 255 K(3) 45 ºF Learning Check

16. © 2014 Pearson Education, Inc. Identify the measurement that has an SI unit. A. John’s height is______.(3) 2.1 m B. The mass of a lemon is _____. (2) 0.145 kg C. The temperature is _____. (2) 255 K Solution