Significant Figures Definition: The digits in a measurement that have values that are known exactly PLUS one digit that has a value that is estimated.

Slides:



Advertisements
Similar presentations
Significant Figures -why we use them -rules for sig. figs. -operations with sig. figs.
Advertisements

Calculations with Significant Figures
Significant Figures.  All measurements are inaccurate  Precision of measuring device  Human error  Faulty technique.
IB Chem I Uncertainty in Measurement Significant Figures.
NOTES: 3.1, part 2 - Significant Figures
Aim: How can we perform mathematical calculations with significant digits? Do Now: State how many sig. figs. are in each of the following: x 10.
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.
How many significant figures?
SIG FIGS Section 2-3 Significant Figures Often, precision is limited by the tools available. Significant figures include all known digits plus one estimated.
1 Significant Figures Significant figures tell us the range of values to expect for repeated measurements The more significant figures there are in a measurement,
Significant Figures Rules and Applications. Rules for Determining Significant Figures 1.) All Non-Zero digits are Significant. 1.) All Non-Zero digits.
Drill – 9/14/09 How many significant figures: Now complete the back of the measurement worksheet from last week (the graduated.
Introduction to Significant Figures & Scientific Notation.
Introduction to Significant Figures & Scientific Notation.
Significant Figures. Significant Digits or Significant Figures We must be aware of the accuracy limits of each piece of lab equipment that we use and.
 Measurement Lab, Sig Figs, SI Units, Book Distribution Chem GT 9/1-2/15.
 Safety Video & Tour Math Assessment Review Measurement and Sig Figs Chem GT 8/28-31/15.
Significant Figures Rules If the decimal is Present, then go to the Pacific side of the measurement, count the first non-zero number and count all other.
Significant Figures. Rule 1: Nonzero numbers are always significant. Ex.) 72.3 has 3 sig figs.
SIG FIGURE’S RULE SUMMARY COUNTING #’S and Conversion factors – INFINITE NONZERO DIGIT’S: ALWAYS ZERO’S: LEADING : NEVER CAPTIVE: ALWAYS TRAILING :SOMETIMES.
Significant Figures!.
Unit 3 lec 2: Significant Figures
Part 2 Significant Figures with Calculations
Significant Figures Notes on PAGE _____. Significant Figures Notes on PAGE _____.
Using Scientific Measurements.
Math of Chem I Textbook Chapter 1 Aim:
1.4 Significant Figures in Calculations
WHY DO SCIENTISTS TAKE MEASUREMENTS ?
Significant Figures Definition: Measurement with Sig Figs:
Significant Figures Sig Figs.
Significant Figures.
Measurement: Significant Figures
Warm –up #2 What is chemistry? Write what you recall about the definition and name 2 areas of study of chemistry.
Aim: Why are Significant Figures Important?
Review of yesterday… How many sig figs are in the following? 0.02
SIG FIGURE’S RULE SUMMARY
Significant Figures.
Significant Digits.
Significant Digits or Significant Figures
(sig figs if you’re cool)
Add to table of contents:
Significant Figures
Rules for Significant Digits
Using Scientific Measurements.
WHY DO SCIENTISTS TAKE MEASUREMENTS ?
Significant figures RULES TO MEMORIZE!.
Intro to Agriculture AAEC – Paradise Valley Fall 2014
Significant Figures All non-zero digits are significant (2.45 has 3 SF) Zeros between (sandwiched)non-zero digits are significant (303 has 3 SF)
Significant Figures CEC 11/28/2018.
Unit 1 lec 3: Significant Figures
Significant Digits.
Section 3-2 Uncertainty in Measurements
Significant Measurements
Super important tool to use with measurements!
Section 2.3 Uncertainty in Data
Significant Digits Calculations.
5. Significant Figures- = represent the valid digits of a measurement and tells us how good your instrument is.
Accuracy vs. Precision & Significant Figures
Accuracy and Precision
Accuracy and Precision
Using Scientific Measurements
Measurement and Calculations
Which of these numbers has the most significant figures E 5
Is it OK to write down all digits on your calculator?
Aim: How do we determine the number of significant figures in a measurement? Warm Up What is the difference between the values of 3, 3.0, and 3.00.
Significant Figures.
Aim: Why are Significant Figures Important?
Significant Figures and Conversions
Presentation transcript:

Significant Figures Definition: The digits in a measurement that have values that are known exactly PLUS one digit that has a value that is estimated.

Measurements Determine Significance 80 70 60 50 40 30 20 10 Read the temperature on the thermometer. Is it: 75°C? 74°C? 74.2°C? How carefully CAN you read it? The instrument itself determines the significance.

Rules for Determining the number of Significant Figures in a Given Measurement If you are given a measurement (i.e. YOU did not measure it), you follow these rules to calculate the number of sig. figs.: All non-zero digits are sig. figs (ex. 1.2300, 3004) Final zeros to right of decimal are sig. figs (ex. 1.0, 1.2300) Zeros surrounded by significant figures are significant (ex. 1.2300, 102, 3004)

Record Number of Significant Figures in Each Measurement

Rule for Addition and Subtraction with Sig. Figs. Round the sum or difference so that it has the SAME number of DECIMAL PLACES as the measurement having the FEWEST decimal places. ex. 2.7 + 3.52 = 6.22 = correct answer shown in red box; what you get on your calculator shown in italics 6.2 ex. 73 - 2.341 = 70.659 = 71 ex. 1001 - 0.099 = 1000.901 = 1001 ex. 2.94 + 0.06 = 3 = 3.00

Rule for Multiplication & Division with Sig. Figs. Express a product or quotient to the same number of significant figures as the multiplied or divided measurement having the fewer total significant figures. ex. 32.43 • 2.17 = 70.3731= correct answer shown in red box; what you get on your calculator shown in italics 70.4 (3 sig. figs.) ex. 9574  45 = 212.7555556 = 210 (2 sig. figs.)

Round Correctly 1) 4.375 g 14.62 g + 327.9 g 2) 3.0024L - 2.3L = A. 347g B. 346.895g C. 346.9g A. 0.7024 L B. 0.7 L C. 0.70 L

Round Correctly Example 2 Example 1 d = 23 g / 4.44 cm3 = a) 5.18018018 g/cm3 b) 5.18 g/cm3 c) 5.2 g/cm3 d) 5 g/cm3 Example 1 5.22 m x 82.7 m = a) 431.694 m2 b) 432 m2 c) 431.7 m2 d) 430 m2

Infinite Number of Significant Digits Some quantities have an infinite number of significant figures because they are definitions rather than measurements. Example, by definition 1 meter = 100.000 00…..cm

sig·nif·i·cant: Definition: Having or expressing a meaning; meaningful. Why are some “figures” insignificant?