Lecture Notes Alan D. Earhart Southeast Community College Lincoln, NE Chapter 1 Chemistry: Matter and Measurement John E. McMurry Robert C. Fay CHEMISTRY Fifth Edition Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 1/2 Chemistry and the Elements
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/3
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/4 Elements and the Periodic Table Periods: 7 horizontal rows. Groups: 18 vertical columns. International standard: 1-18 US system: 1A-8A, 1B-8B
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/5 Elements and the Periodic Table Main Groups columns 1A-2A (2 groups) columns 3A-8A (6 groups) Transition Metals: 3B-2B (8 groups, 10 columns). Inner Transition Metals: 14 groups between 3B and 4B. lanthanides actinides
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/6 Elements and the Periodic Table Metals: Left side of the zigzag line in the periodic table (except for hydrogen). Nonmetals: Right side of the zigzag line in the periodic table. Semimetals (metalloids): Tend to lie along the zigzag line in the periodic table.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/7 Elements and the Periodic Table Alkali Metals
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/8 Elements and the Periodic Table Alkaline Earth Metals
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/9 Elements and the Periodic Table Halogens
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/10 Elements and the Periodic Table Noble Gases
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/11 Some Chemical Properties of the Elements Intensive Properties: Independent of sample size. temperature melting point Extensive Properties: Dependent on sample size. length volume
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/12 Some Chemical Properties of the Elements Physical Properties: Characteristics that do not involve a change in a sample’s chemical makeup. Chemical Properties: Characteristics that do involve a change in a sample’s chemical makeup.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/13 Experimentation and Measurement Système Internationale d´Unités All other units are derived from these fundamental units.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/14
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/15 Measuring Mass Mass: Amount of matter in an object. Matter: Describes anything with a physical presence—anything you can touch, taste, or smell. Weight: Measures the force with which gravity pulls on an object.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/16 Measuring Length Meter 1790: One ten-millionth of the distance from the equator to the North pole along a meridian running through Paris, France. 1889: Distance between two thin lines on a bar of platinum-iridium alloy stored near Paris, France. 1983: The distance light travels in 1/299,792,458 of a second.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/17
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/18 Measuring Temperature (°F - 32 °F) 5 °C 9 °F °C =°C + 32 °F 9 °F 5 °C °F = K = °C
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/19 Derived Units: Measuring Volume
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/20
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/21 Derived Units: Measuring Density density = volume mass solids- cm 3 liquids- mL gases- L Typical volume units
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/22 Accuracy, Precision, and Significant Figures Accuracy: How close to the true value a given measurement is. Single measurement: percent error Series of measurements: average Precision: How well a number of independent measurements agree with each other. Characterized by the standard deviation.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/23 Accuracy, Precision, and Significant Figures good accuracy good precision Mass of a Tennis Ball
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/24 Accuracy, Precision, and Significant Figures good accuracy poor precision Mass of a Tennis Ball
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/25 Accuracy, Precision, and Significant Figures poor accuracy poor precision Mass of a Tennis Ball
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/26 Accuracy, Precision, and Significant Figures Significant figures: The number of meaningful digits in a measured or calculated quantity. They come from uncertainty in any measurement. Generally the last digit in a reported measurement is uncertain (estimated). Exact numbers and relationships (7 days in a week, 30 students in a class, etc.) effectively have an infinite number of significant figures.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/27 Accuracy, Precision, and Significant Figures length = 1.74 cm cm 1.7 cm < length < 1.8 cm
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/28 Accuracy, Precision, and Significant Figures cm4 SF Rules for counting significant figures (left-to-right): 1.Zeros in the middle of a number are like any other digit; they are always significant.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/29 Accuracy, Precision, and Significant Figures g3 SF(or 6.61 x g) Rules for counting significant figures (left-to-right): 1.Zeros in the middle of a number are like any other digit; they are always significant. 2.Zeros at the beginning of a number are not significant (placeholders).
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/30 Accuracy, Precision, and Significant Figures K5 SF Rules for counting significant figures (left-to-right): 1.Zeros in the middle of a number are like any other digit; they are always significant. 2.Zeros at the beginning of a number are not significant (placeholders). 3.Zeros at the end of a number and after the decimal point are always significant.
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/31 Accuracy, Precision, and Significant Figures Rules for counting significant figures (left-to-right): 1.Zeros in the middle of a number are like any other digit; they are always significant. 2.Zeros at the beginning of a number are not significant (placeholders). 3.Zeros at the end of a number and after the decimal point are always significant. 4.Zeros at the end of a number and after the decimal point may or may not be significant. 34,200 m? SF
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/32 Rounding Numbers Math rules for keeping track of significant figures: Multiplication or division: The answer can’t have more significant figures than any of the original numbers gal 278 mi = 23.8 mi/gal 4 SF 3 SF
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/33 Rounding Numbers Math rules for keeping track of significant figures: Multiplication or division: The answer can’t have more significant figures than any of the original numbers. Addition or subtraction: The answer can’t have more digits to the right of the decimal point than any of the original numbers decimal places 5 decimal places 2 decimal places
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/34 Rounding Numbers Rules for rounding off numbers: 1.If the first digit you remove is less than 5, round down by dropping it and all following numbers = 5.66
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/35 Rounding Numbers Rules for rounding off numbers: 1.If the first digit you remove is less than 5, round down by dropping it and all following numbers. 2.If the first digit you remove is 6 or greater, round up by adding 1 to the digit on the left = 5.7
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/36 Rounding Numbers Rules for rounding off numbers: 1.If the first digit you remove is less than 5, round down by dropping it and all following numbers. 2.If the first digit you remove is 6 or greater, round up by adding 1 to the digit on the left. 3.If the first digit you remove is 5 and there are more nonzero digits following, round up = 5.665
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/37 Rounding Numbers Rules for rounding off numbers: 1.If the first digit you remove is less than 5, round down by dropping it and all following numbers. 2.If the first digit you remove is 6 or greater, round up by adding 1 to the digit on the left. 3.If the first digit you remove is 5 and there are more nonzero digits following, round up. 4.If the digit you remove is a 5 with nothing following, round down =
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/38 Calculations: Converting from One Unit to Another Dimensional analysis: A method that uses a conversion factor to convert a quantity expressed in one unit to an equivalent quantity in a different unit. Conversion factor: States the relationship between two different units. original quantity x conversion factor = equivalent quantity
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/39 Calculations: Converting from One Unit to Another 1 m = in Conversion factor: Relationship: 1 m in or in 1 m converts m to in converts in to m
Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/40 Calculations: Converting from One Unit to Another in 1 m 69.5 in = 1.77 mx equivalent quantitystarting quantity conversion factor