Mr. Palermo's Flipped Chemistry Classroom
  • Home
  • Chemistry Units
    • Advice from former students
    • Demonstrations
    • Edpuzzle Videos
    • Course Documents
    • Unit 1: The Nature of Science
    • Unit 2: Intro to Matter
    • Unit 3: Atomics
    • Unit 4: Moles & Stoichiometry
    • Unit 5: Periodic Table
    • Unit 6: Chemical Bonding
    • Midterm Review
    • Unit 7: Heat
    • Unit 8: Gases
    • Unit 9: Solutions
    • Unit 10: Kinetics & Equilibrium
    • Unit 11: Organic Chemistry
    • Quarter 3 Exam Review
    • Unit 12: Acids and Bases
    • Unit 13: Electrochemistry
    • Unit 14: Nuclear Chemistry
    • Regents Chemistry Review
  • Modeling Chemistry Units
    • NYSSLS Sample Unit
    • What is Modeling Instruction
    • Edpuzzle Videos
    • Demonstrations
    • Unit 1: Particles and Measurement
    • Unit 2: Particles in Motion
    • Unit 3: Energy and States of Matter
    • Unit 4: Types of Matter
    • Unit 5: Attractive Forces
    • Unit 6: Subatomic Particles
    • Unit 7: Periodicity
    • Unit 8: Bonding & IMF'S
    • Unit 9: Moles & Stoichiometry
    • Unit 10 Kinetics & Equilibrium
    • Unit 11 Acids and Bases
    • Unit 12 Electrochemistry
    • Unit 13 organic chemistry
  • Virtual Labs
    • Virtual Lab Precision and Significant Figures
    • Virtual Lab: Flame Test & Spectroscopy
    • Inquiry Lab Spectroscopy >
      • Inquiry Flame Test
      • Unknown Flame Test
      • Inquiry Emission Spectrum
      • Unknown Emission Spectrum
    • Virtual Lab: Bonding and Molecular Geometry
    • Virtual Lab Hydrates
    • Virtual Lab: Activity Series
    • Virtual Lab Conductivity
    • Virtual LeChateliers Principle
    • virtual lab: Acid Base Inquiry
    • Virtual Lab: Electrochemical Cells
    • Virtual Lab: Titration
  • Contact
  • Publications
  • Teacher Resources
    • Email for Google Drive Access
    • Access my Edpuzzle Videos
    • NYSSLS Facebook Group
    • Long Island Chemistry Teacher Support Group
    • NYSSLS/NGSS Units
    • Sample Flipped NYSSLS Unit
    • Flipping the Classroom
    • Youtube Channel
    • Demonstrations
    • Phenomenon Database
  • About Me

Virtual Lab:  Precision and Significant Figures

Background: 

Uncertainty in Measurement:

It is important to realize that any measurement will always contain some degree of uncertainty.  The uncertainty of the measurement is determined by the scale of the measuring device.  The smaller the unit you use to measure with, the more precise the measurement is.


Precision vs. Accuracy:

Precision- how close individual measurements agree with each other.
Accuracy- how close individual measurements agree with the true or accepted value.

Picture
Picture
Accurate number = small errors
Precise number = small uncertainty 

In General, the uncertainty of a measurement is determined by the precision of the measuring device. The smaller the unit you use to measure with, the more precise the measurement is.  For example a 100mL graduated cylinder with 1mL graduation will have an uncertainty of +/- 0.1 mL.  When making a measurement you must always estimate 1 place past the smallest divison.

Significant Figures 

An alternative method of regarding uncertainty.  In any measurement, the number of significant figures is critical. The number of significant figures is the number of digits believed to be correct by the person doing the measuring. It includes one estimated (uncertain) digit.

Rules for Working with Significant Figures: 

1.  Leading zeros are never significant. 
Trapped zeros are always significant. 
Trailing zeros are significant only if the decimal point is specified. 
Hint: Change the number to scientific notation. It is easier to see. 

2.  Addition or Subtraction:
The last digit retained is set by the first doubtful digit. 
3.  Multiplication or Division:
The answer contains no more significant figures than the least accurately known number. 


Pre Lab:  
                                  How Many Significant Figures Do These Numbers Contain?
Picture

Click the link to check your answers:  Answers



Objective:

The aim of this lab is to practice recording measurements with the correct precision.


Procedure:

Several stations have been set up in this virtual lab.  For each station, click on the measuring tool link, read the directions, and read the measurements according to the directions.  Record this measurements with the correct units in the slot in your data table that corresponds to the station number.  Remember to estimate to 1 place of uncertainty for each measurement.  Then determine the number of significant figures for each measurement.
Picture
Lab Quiz:

1. Round off the following measurement to three significant figures.   
    1.296 g


2. How many significant figures are there in the following measurement?
    2020 g



3. Round off the following measurement to three significant figures. 
    5.658 grams
CONNECT:   
Picture
Picture
Picture
Picture
Picture
WWW.MRPALERMO.COM
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.