Precision and Accuracy of Measurement An AP Biology Case Study.

Slides:

Advertisements

Similar presentations

Notebook p 29 Three Ways To Determine Density. 1) Regular Objects 1.Measure the each side of the block in centimeters. Calculate volume in cm³: multiply.

Advertisements

Topic: Final Exam Review Aim: Let’s review Scientific Method and Measurement Do Now: Fill in Measurement Units Chart HW: Cells and Cell Transport Review.

Recycling Plastics Lab. Recycling Plastics Lab (1/8) How can we separate plastics efficiently using the differing densities of different types of plastics?

Ocean Density Three Investigations. Investigation 1 – Which is denser: fresh water or salt water? Read the question carefully. – What is the independent.

Will the ball float on liquid mercury?

Periodic Trends in Density Required Laboratory Skills.

 To solve a problem, you use what you already know to figure out something you want to know.

Laboratory Equipment. Erlenmeyer Flasks Beakers.

Experimental errors.

Topic 11: Measurement and Data Processing

Catalyst If I have a can of coke and I put it in a bowl of water, will it sink or float? What about a can of diet coke? Convert 3 mL to ounces A scientist.

But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control.

Flashback Convert 2.58 m to kilometers. Accuracy and Precision Accuracy- the closeness of measurements to the correct value of the quantity measured.

Error, Accuracy, Precision, and Standard Deviation Notes.

Exam 1 review. List the 7 diatomic molecules Chemical and physical properties Chemical and physical changes Pure substances Characteristics of matter.

MEASUREMENT OF VOLUME. OVERVIEW First some general principles Then, more detail about micropipettes.

Density All substances have different densities, therefore, you can identify a substance if you know its density The formula to calculate something’s density.

Lab Practical Practice *use correct number of significant figures when solving!

Content Standard 1 Select appropriate laboratory glassware, balances, time measuring equipment, and optical instruments to conduct an experiment.

Tools of the Trade Common Lab Equipment in a Biotech Classroom.

Density A Physical Property of Matter. What is Density? Density is the amount of mass in a given volume. Density is the amount of mass in a given volume.

Analysis The analysis section describes the data and identifies and discusses trends in the data. It is very important to directly use the data to support.

Math and Measurement. Significant Figures Significant Zeros 1.Leading zeros are never significant 2.Trailing zeros only count if there’s a decimal point.

Density. Different substances have different densities. The density of a material does not depend on the size or amount of the substance you have. Density.

DENSITY A Quantitative Physical Property. Which Weighs More?? A Pound of Lead -or- A Pound of Feathers.

Density. Density is a ratio of mass to volume of an object. D= m / v (density = mass / volume) Density is measured in g/mL (grams per milliliter). Density.

Accuracy and Precision. Remember these definitions? ► Accuracy – a description of how close a measurement is to the true value of the quantity measured.

Topic 1 Tools of the Biology Laboratory Exercise I. The spectrophotometer. Exercise II. Liquid Measurements. Exercise III. Sedimentation and Centrifugation.

Welcome to Chemistry 116! Lab Safety and Proper Procedure Labs 1 & 2.

Density Equation m V d SymbolVariableUnits dDensityg/cm 3 or g/mL mMassgrams VVolumecm 3 or mL.

Density How close together the molecules of an object are. How Dense the molecules are. “Dense forest” = thick, hard to see through.

What is the formula? How can density be used to identify materials?

Laboratory Report Format You will have the option of either handwriting or typing your lab reports. You will be graded on the following: 1. Accuracy of.

Mystery Cubes Using Density to Identify Matter. What is Density?

Accuracy & Precision Tuesday, August 25th, 2015.

Density Section 2.1 Measurement of how packed or crowed object is Ratio of mass to volume.

Topic 1 Tools of the Biology Laboratory Exercise I. The spectrophotometer. Exercise II. Liquid Measurements. Exercise III. Sedimentation and Centrifugation.

READING BETWEEN THE LINES Estimate one place on non digital equipment. (rulers, graduated cylinders) 6 7 cm 6.42 cm If it is exactly on the line 6.60 cm.

Bell work What does density tell you about an object?

LABORATORY ACTIVITIES FOR REGENTS CHEMISTRY. Many laboratory activities require measurements. Science uses the S.I. (Metric System) of measurements.

Why is there a need for a standard system of measurement? People in the world need to be able to agree on specific quantities.

READING GRADUATED EQUIPMENT Read each digit that is certain, plus one digit that is uncertain To determine the certain digits, identify the most accurate.

Quantitative analysis of biological samples.

Significant Figures in Calculations

How does the volume of snow compare to the volume of liquid from the melted snow ?

Take out a sheet of paper and label with the heading on this slide.

Measuring Tools Measurement Tools Units Length Mass Volume Temperature

Mole and Stoichiometry Mini-Lab

Mass, Volume & Density.

Density D= Mass_ Volume Mass: put matter on balance Volume:

Determining if an object will float or sink

volume and density measurement for test on Tuesday.

Pipette Technique.

Lab Equipment: Collecting Data

Accuracy, Precision, Percent Error, Significant Figures and Rounding

Accuracy and Precision

Accuracy & Precision Friday, September 2nd, 2016.

Significant Figures in Calculations

Accuracy and Precision

Title: Measurement Lab

Measurement Lab.

JEOPARDY Scientific Method Laws and Theories Metric system Measurement

What amount of heat is required to increase the temperature of 75

A closer look at the physical property of Density

Accuracy and Precision

When you finish your quiz, Read pages 49-53, Section 2

Lab 8 The Density of Water Purpose Background PART 1

Presentation transcript:

Precision and Accuracy of Measurement An AP Biology Case Study

Validation Before equipment is used in a laboratory setting, its validity must be determined. As an AP biology student it is important to: Recognize how statistics may be used as a part of the validation process. Learn to use various tools to measure volume. Learn to upload data in google docs and analyze large data sets in Excel.

Salinity of Water The salinity of water is one factor in the determination of which organisms can grow. You are working as the manager of a sewage treatment plant. The bacteria necessary to break down raw sewage do not grow in high salinity. Recent high rains have caused seawater to infiltrate your systems. You have tried to mitigate the situation and want to determine if you now have pure H 2 O flowing through your system’s in-flow pipes. Before you test your water…you must validate your equipment using pure water.

Techniques Accuracy : You have a balance that measures to the thousands of a gram. You have various tools to measure volume in mL You know the density of pure water is 1 g/mL. What measure can you use to determine the accuracy of each measurement tool?

Techniques Precision You have the following tools to use to measure volume. Since you are testing for the first time, you want to figure out which tool is most precise so you can choose the appropriate tool later. What measurement can you use to evaluate the precision of each measurement tool?

Tools 10 mL graduated cylinder (measures to 0.2 ml) 1 ml plastic pipette (measures to 0.25 ml) 1 ml graduated pipette (measures to 0.1 ml) 1 ml micropipette (measures to ml; but not suggested for measuring amounts below 200 ul) Which tool do you think will produce the most accurate results? Which tool do you think will produce the most precise results?

Conclusions Which tool was most accurate? Explain your conclusion based on the data. Which tool was most precision? Explain your conclusion based on the data Which tool would you use to validate your water sample and why? Why is validating equipment an important part of the experimental process? What sources of error may have resulted in your validation process?