Accuracy vs. Precision Accuracy is a description of how close a measurement is to the correct or accepted value of the quantity measured. Ex: if the correct.

Slides:

Advertisements

Similar presentations

1.2 Measurements in Experiments

Advertisements

Section 1: Significant Figures

Using Scientific Measurements.

SIGNIFICANT FIGURES.

Significant Figures, and Scientific Notation

SIGNIFICANT FIGURES. What are SIG FIG’S Digits that carry meaning contributing to its precision. They help make our “precision” more accurate Precision-the.

Objectives The student will be able to: ● Distinguish between accuracy and precision ● Use significant figures in measurements and calculations.

Ms. Pollock Significant Figures  Numbers in math class considered to be exact – produced by definition, not by measurement  Measurements.

Significant Figures.

IB Chem I Uncertainty in Measurement Significant Figures.

Significant Figures/Significant Digits

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.

A measured value Number and unit Example 6 ft.. Accuracy How close you measure or hit a true value or target.

SIGNIFICANT FIGURES. ACCURACY VS. PRECISION  In labs, we are concerned by how “correct” our measurements are  They can be accurate and precise  Accurate:

Measurement book reference p Accuracy  The accuracy of the measurement refers to how close the measured value is to the true or accepted value.

Cup of coffee = ~ 200 ml Add drop of H 2 O = 0.05 mL New volume: ~200 mL or mL?? If you say you imply that the volume of the initial cup.

Significant Digits p. 940 – 941 or significant figures or sigfigs or sf.

Unit 1- Units and Measurement Chemistry. Scientific Notation, Measurement, Accuracy, Precision, Error.

Scientific Measurements “measurement” could be defined as the process or the result of determining the magnitude of a quantity. Measurements can be made.

Scientific Method, Calculations, and Values. Accuracy Vs. Precision Measuring and obtaining data experimentally always comes with some degree of error.

ACCURACY A description of how close measurement is to the true or accepted value of a measurement. Error or Absolute Error = Observed value – accepted.

Significant Figures. The Basics  All nonzero digits are significant  Ex: 1.2 – 2 significant digits  Ex: has 5 significant digits  Zeroes between.

Scientific Measurements Calculations, and Values.

Problem of the Day x m x m x 10 8 km – 3.4 x 10 7 m 3. (9.21 x cm)(1.83 x 10 8 cm) 4. (2.63 x m) / (4.08 x.

Accuracy, Precision, Significant Figures

Significant Figures. Significant figures are the digits in any measurement that are known with certainty plus one digit that is uncertain. Number of significant.

Significant Digits. l Significant figures are extremely important when reporting a numerical value. l The number of significant figures used indicates.

2.3 Using Scientific Measurements. Accuracy vs. Precision  Accuracy- closeness of measurement to correct or accepted value  Precision- closeness of.

Scientific Notation, Significant Figures & Significant Digits SCH3U.

Chapter 2 Measurements and Calculations Or It all adds up!

The significant figures in a measurement Consist of all the digits known with certainty plus one final digit, which is uncertain or is estimated. What.

Note the 4 rules When reading a measured value, all nonzero digits should be counted as significant. There is a set of rules for determining if a zero.

Significant Figures. This can be difficult so … This can be difficult so … Hold on tight for a wild ride Hold on tight for a wild ride.

Significant Digits and Scientific Notation

Significant Figures.

Measurement: Significant Figures. Significant Figures  Significant Figures (sig. figs.): the number of digits that carry meaning contributing to the.

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.

Chemistry Using and Expressing Measurements Section 3.1.

Chapter 2 Measurements and Calculations Or It all adds up!

Using Scientific Measurements.

Significant Figures.

BELLWORK 9/13/16 1 Tm = 1012 m 1mm = 10-3 m 1Mm = 106 m

Uncertainty in Measurement

Uncertainty in Measurement

Our Friends, the Significant Figures

Accuracy and Precision

Using Scientific Measurements.

Significant Figures Any digit in a measurement that is known with certainty plus one final digit, which is somewhat uncertain or estimated.

Chapter 2 Accuracy vs Precision.

Chemistry 02/06-02/07/17.

Significant Figures.

Uncertainty in Measurement

Measurement book reference p

BELLWORK 9/2/15 How does a scientist reduce the frequency of human error and minimize a lack of accuracy? A. Take repeated measurements B. Use the same.

Accuracy and Precision

Significant Figures, and Scientific Notation

Significant Figures/Accuracy and Precision

Significant Figures.

Using Scientific Measurements

Section 2-3 Using Measurements

CH. 2 - MEASUREMENT I. Using Measurements.

Accuracy vs. Precision & Significant Figures

Accuracy and Precision

Scientific Measurements

SIGNIFICANT FIGURES.

SCIENTIFIC MEASUREMENT

Significant Figures (Sig figs)

Accuracy and Precision

Our Friends, the Significant Figures

Presentation transcript:

Accuracy vs. Precision Accuracy is a description of how close a measurement is to the correct or accepted value of the quantity measured. Ex: if the correct value is 5, then 4.95 is accurate. 2 is not accurate.

Accuracy vs. Precision Precision is the degree of exactness of a measurement. Ex: If you have three measurements: 5.10, 4.95, and 4.98, they are precise. If a measurement is precise, it may not be accurate!

Significant Figures Significant figures are a way to help keep track of imprecise measurements. Significant figures are the digits that are known for certain, as well as the first digit that is uncertain. Ex: 18.2 cm has 3 significant figures. Two are known for certain, 0.2 is uncertain. It is uncertain because the digit after it is not known.

Significant Figures Rules for determining significant figures: - All whole numbers (except for zero) are significant Zeros between other nonzero digits are significant Ex: 50.3 has 3 significant figures 3.0025 has five significant figures Zeros in front of nonzero digits are NOT significant Ex: 0.892 has 3 significant figures 0.0008 has 1 significant figure Zeros that are at the end of a number and to the right of a decimal are significant. - Ex: 57.00 has four significant figures 2.000 has four significant figures