Chapter 1 Chemical Foundations. Section 1.4 Uncertainty in Measurement 2 Return to TOC Copyright © Cengage Learning. All rights reserved Precision and.

Slides:

Advertisements

Similar presentations

The volume we read from the beaker has a reading error of +/- 1 mL.

Advertisements

Forensic Science.   Part 1 - number  Part 2 - scale (unit)  Examples:  20 grams  6.63 x Joule seconds Measurement - quantitative observation.

Measurement and Calculations in Chemistry

Uncertainty and Significant Figures Cartoon courtesy of Lab-initio.com.

Chapter One: CHEMICAL FOUNDATIONS. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 1 | Slide 2 Chemistry: An Overview A main challenge.

Measurements and Calculations

Significant Figures PP 6a Honors Chemistry.

Rules for Counting Significant Figures - Details Nonzero integers always count as significant figures has 4 sig figs.

Chapter 1 Chemical Foundations. Chapter 1 Table of Contents Return to TOC Copyright © Cengage Learning. All rights reserved 1.1 Chemistry: An Overview.

Chapter 1 Chemical Foundations.

Measurements and Calculations

Chapter 2 The Metric System

Significant Figures.

1. To show how very large or very small numbers can be expressed in scientific notation 2. To learn the English, metric, and SI systems of measurement.

MeasurementsandCalculations. Numbers Numbers in science are different than in math. Numbers in science always refer to something grams 12 eggs.

Chapter 1.5 Uncertainty in Measurement. Exact Numbers Values that are known exactly Numbers obtained from counting The number 1 in conversions Exactly.

Section 2.3 Measurement Reliability. Accuracy Term used with uncertainties Measure of how closely individual measurements agree with the correct or true.

Uncertainty in Measurements: Using Significant Figures & Scientific Notation Unit 1 Scientific Processes Steinbrink.

The Scientific Method 1. Using and Expressing Measurements Scientific notation is written as a number between 1 and 10 multiplied by 10 raised to a power.

Chapter 1 Chemical Foundations. Chapter 1 Table of Contents Return to TOC Copyright © Cengage Learning. All rights reserved 1.1 Chemistry: An Overview.

Chapter 1 Chemical Foundations. Chapter 1 Table of Contents Return to TOC Copyright © Cengage Learning. All rights reserved 1.1 Chemistry: An Overview.

Chapter 2 Measurements and Calculations. Chapter 2 Table of Contents Return to TOC Copyright © Cengage Learning. All rights reserved 2.1 Scientific Notation.

Measurement and Significant Figures. Precision and Accuracy What is the difference between precision and accuracy in chemical measurements? Accuracy refers.

Measurements and Calculations 1. To show how very large or very small numbers can be expressed in scientific notation 2. To learn the English, metric,

Honors Chemistry I. Uncertainty in Measurement A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty.

Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Steps in the Scientific Method 1.Observations  quantitative  qualitative 2.Formulating.

Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Steps in the Scientific Method 1.Observations  quantitative  qualitative 2.Formulating.

SIGNIFICANT FIGURES Measured Data Counted & Defined Data (exact numbers) Calculated Data –Multiplication & Division –Addition & Subtraction.

Unit 1 Chapter 2. Common SI Units SI System is set-up so it is easy to move from one unit to another.

Objectives To learn how uncertainty in a measurement arises

1 Measurements. 2 Nature of Measurement Measurement - quantitative observation consisting of 2 parts Part 1 - number Part 2 - scale (unit) Part 2 - scale.

Objectives To learn how uncertainty in a measurement arises

Measurements & Calculations Chapter 2. Nature of Measurement Measurement - quantitative observation consisting of two parts: Part 1 - number Part 2 -

Uncertainty in Measurement

Section 5: Significant Figures Cartoon courtesy of Lab-initio.com Unit 1: Matter & Measurement.

Accuracy and Precision Accuracy and Precision A MEASURE of your SUCCESS!

Scientific Notation & Significant Figures in Measurement.

Uncertainty in Measurement A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty. Significant figures.

Uncertainty and Significant Figures Cartoon courtesy of Lab-initio.com.

V. Limits of Measurement 1. Accuracy and Precision.

Uncertainty in Measurement A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty.

Unit 0: Observation, Measurement and Calculations Cartoon courtesy of NearingZero.net.

Section 5.1 Scientific Notation and Units Steven S. Zumdahl Susan A. Zumdahl Donald J. DeCoste Gretchen M. Adams University of Illinois at Urbana-Champaign.

 1. Nonzero integers. Nonzero integers always count as significant figures. For example, the number 1457 has four nonzero integers, all of which count.

Chemistry I. Precision and Accuracy Accuracy refers to the agreement of a particular value with the true value. Precision refers to the degree of agreement.

Section 5.2 Uncertainty in Measurement and Significant Figures 1.To learn how uncertainty in a measurement arises 2.To learn to indicate a measurement’s.

Significant Figures When we take measurements or make calculations, we do so with a certain precision. This precision is determined by the instrument we.

Chapter 1 Significant Figures.

How big is the beetle? Measure between the head and the tail!

Uncertainty and Significant Figures

How big is the beetle? Measure between the head and the tail!

Uncertainty and Significant Figures

OPENING ROUTINE A material will float on the surface of a liquid if the material has a density less than that of the liquid. Given that the density of.

Uncertainty and Significant Figures

Analyzing Data Chemistry Chapter 2.

Math Toolkit ACCURACY, PRECISION & ERROR.

Significant Figures.

Measurements and Calculations

Uncertainty and Significant Figures

Uncertainty and Significant Figures

Measurements and Calculations.

Accuracy and Precision

Accuracy and Precision

Uncertainty and Significant Figures

Numbers From Measurements

Uncertainty and Significant Figures

Uncertainty and Significant Figures

Significant Figures (Sig figs)

Presentation transcript:

Chapter 1 Chemical Foundations

Section 1.4 Uncertainty in Measurement 2 Return to TOC Copyright © Cengage Learning. All rights reserved Precision and Accuracy Accuracy Agreement of a particular value with the true value. Precision Degree of agreement among several measurements of the same quantity.

Section 1.4 Uncertainty in Measurement 3 Return to TOC Copyright © Cengage Learning. All rights reserved Precision and Accuracy

Section 1.4 Uncertainty in Measurement 4 Return to TOC Copyright © Cengage Learning. All rights reserved A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty. Record the certain digits and the first uncertain digit (the estimated number).

Section 1.4 Uncertainty in Measurement 5 Return to TOC Copyright © Cengage Learning. All rights reserved Measurement of Volume Using a Buret The volume is read at the bottom of the liquid curve (meniscus). Meniscus of the liquid occurs at about mL.  Certain digits:  Uncertain digit: 20.15

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved 1.Nonzero integers always count as significant figures.  3456 has 4 sig figs (significant figures). Rules for Counting Significant Figures

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved There are three classes of zeros. a.Leading zeros are zeros that precede all the nonzero digits. These do not count as significant figures.  has 2 sig figs. Rules for Counting Significant Figures

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved b.Captive zeros are zeros between nonzero digits. These always count as significant figures.  has 4 sig figs. Rules for Counting Significant Figures

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved c.Trailing zeros are zeros at the right end of the number. They are significant only if the number contains a decimal point.  has 4 sig figs.  150 has 2 sig figs. Rules for Counting Significant Figures

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved 3.Exact numbers have an infinite number of significant figures.  1 inch = 2.54 cm, exactly.  9 pencils (obtained by counting). Rules for Counting Significant Figures

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved Example  300. written as 3.00 × 10 2  Contains three significant figures. Two Advantages  Number of significant figures can be easily indicated.  Fewer zeros are needed to write a very large or very small number. Exponential Notation

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved 1.For multiplication or division, the number of significant figures in the result is the same as the number in the least precise measurement used in the calculation × 5.5 =  7.4 Significant Figures in Mathematical Operations

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved 2.For addition or subtraction, the result has the same number of decimal places as the least precise measurement used in the calculation. Significant Figures in Mathematical Operations

Section 1.5 Significant Figures and Calculations Return to TOC Copyright © Cengage Learning. All rights reserved Concept Check You have water in each graduated cylinder shown. You then add both samples to a beaker (assume that all of the liquid is transferred). How would you write the number describing the total volume? 3.1 mL What limits the precision of the total volume?