Measuring and Calculating X  Chapter 2  Measuring and Calculating HOMEWORK DUE: Turn in Lab 5 Make sure each group member’s name is on the front page. HW 8: Outline Chap 2 Due Friday: HW 9; handout from sciencespot.net

Math Problem Solving Identify: What do you know from the problem. Underline it! Identify: What are you trying to find. Underline it! Identify what equations or conversion factors match what you know and what you want to know. Write out the equation – plug in the numbers – then estimate the answer. Finally, press the correct buttons on your calculator – and you are done!

Key Terms: 15 points, Turn in Today Percent error Significant Digits Derived units density (g/cm3) or (g/ml) counting number prefix kilo deci milli micro Mass (kg) Weight (lbs) Volume (ml or L) balance (g) length (cm or m) time (sec) temperature (oC or K) Accuracy Precision Find the definition for each, write a sentence using the word correctly.

Scientific notation: Write the decimal represented by the scientific notation. 0.000001 0.00001 0.0001 0.001 0.01 0.1 1 10 100 1000 10000 1 x 10-6 1 x 10-5 1 x 10-4 1 x 10-3 1 x 10-2 1 x 10-1 1 x 10-0 1 x 101 1 x 102 1 x 103 1 x 104

Prefixes Mega (M) Million 1 000 000 1x106 kilo (k) thousand 1 000 base unit ( ) one 1 1 x 100 deci (d) one tenth 0.1 1 x 10-1 centi (c) one hundredth 0.01 1 x 10-2 milli (m) one thousandth 0.001 1 x 10-3

practice: Use the prefix to make this number 1.00 1,000 grams 0.01 grams 0.1 liters 1,000 liters 1 x 103 m 1 x 10-3 m 1 x 100 g 1 x 10-2 liters 1 kilogram 1 centigram 1 deciliter 1 kiloliter 1 kilometer 1 millimeter 1 gram 1 centiliter

Practice converting between units. 1 m 20 cm = ____ m 3000 mm = ______ m 2.85 m = ________km 62.4 g = ________kg 19.5 L = ______cL 0.12 L = ______mL 0.305 L = _____mL 0.20 20 cm 100 cm 3. cm 3000 mm 1 m 1000 mm mm

Practice converting between units. 20 cm = ____ m 3000 mm = ____m 2.85 m = ______km 62.4 g = ______kg 19.5 L = ______cL 0.12 L = ______mL 0.305 L = _____mL 0.2 3 1 km 2.85 m 2.85 x 10-3 1000 m m 6.24 x 10-2 62.4 g 1.00 kg 1000 g g

Practice converting between units. 20 cm = ____ m 3000 mm = ____m 2.85 m = ______km 62.4 g = ______kg 19.5 L = ______cL 0.12 L = ______mL 0.305 L = _____mL 0.2 3 100 cL 19.5 L 2.85 x 10-3 1 L 6.24 x 10-2 0.12 L 1000 mL 1950 120 L 1.0 L 305

Metric Conversions the easy way! 1 1000 mg = _____ g 1L = _____mL 160 cm = _____ mm 14 km = ______m 0.109 109 g = _______ kg 250 m = _____km 56 cm O 6 m 7g O 698 mg 0.25 1000 1600 < 14000 < Practice: Notes, 1 – 21 are homework

Density: how much mass per unit volume? Volume is measured in three dimensional quantities: mL, L, cm3, m3,… Mass is measured in g, kg,… Density is a “derived unit” of g/ml or g/cm3 or g/L or kg/L,…. Mass = Density x Volume Density = Mass Volume Volume = Mass Density

Density = mass/volume What is the density of a piece of concrete that has a mass of 8.76g and a volume of 3.07 cm3 Density = Mass Volume mass = 8.76 g density = ? Volume = 3.07 cm3 Mass = Density x Volume density = 8.76 g 3.07 cm3 = 2.85 g/cm3 Volume = Mass Density

Density = mass/volume Limestone has a density of 2.72 g/cm3. What is the mass of 24.9 cm3 of limestone? Density = Mass Volume mass = ? density = 2.72 g/cm3 Volume = 24.9 cm3 Mass = Density x Volume Volume = Mass Density mass = (2.72 g/cm3)(24.9 cm3) = 67.7 g