Measurement Error
Presentation
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Chemistry
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9th - 12th Grade
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Practice Problem
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Medium
Standards-aligned
Matthew Martino
Used 35+ times
FREE Resource
13 Slides • 9 Questions
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Measurement Error
"To err is human, to forgive is divine"
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Open Ended
Using a word or a phrase, what do you think when you hear the word "error" ?
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Error in a real-world science example
The Digital Balance
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Multiple Choice
Your lab has 3 digital balances and you periodically check them against a 50.00 gram mass standard to monitor their accuracy and precision.
You place the 50.00 g weight on each balance three times and record the masses they read.
Balance #1: 49.67 g ; 50.32 g ; 49.85 g
Balance #2: 47.83 g ; 58.35 g ; 36.87 g
Balance #3: 53.24 g ; 53.25 g ; 53.15 g
Which balance would be described as precise, but not accurate?
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Multiple Choice
Your lab has 3 digital balances and you periodically check them against a 50.00 gram mass standard to monitor their accuracy and precision.
You place the 50.00 g weight on each balance three times and record the masses they read.
Balance #1: 49.67 g ; 50.32 g ; 49.85 g
Balance #2: 47.83 g ; 58.35 g ; 36.87 g
Balance #3: 53.24 g ; 53.25 g ; 53.15 g
Which balance would be described as both accurate and precise?
8
Multiple Choice
Your lab has 3 digital balances and you periodically check them against a 50.00 gram mass standard to monitor their accuracy and precision.
You place the 50.00 g weight on each balance three times and record the masses they read.
Balance #1: 49.67 g ; 50.32 g ; 49.85 g
Balance #2: 47.83 g ; 58.35 g ; 36.87 g
Balance #3: 53.24 g ; 53.25 g ; 53.15 g
Which balance would be described as neither accurate nor precise?
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Error
All measurements have some error
Error is based on accuracy
Error is the difference between a measured value and the accepted value
Error = measured - accepted
Accepted values are considered exact and true. (sometimes called the theoretical value)
Examples of accepted values are the densities for elements listed in Table S of your Reference Tables.
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Found on the back of your Reference Tables (Table T)
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Fill in the Blanks
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Multiple Choice
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Where does expairimentle erorr come from?
Human error (try to minimize)
Equipment inconsistencies and/or degree of precision
Changes to conditions such as temperature, pressure, humidity, etc.
Age of chemicals
Aliens... j/k
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Multiple Choice
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Multiple Choice
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Poll
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Measurement Error
"To err is human, to forgive is divine"
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