Unit 1-Concept 1: Measurment Flashcards
Observation
objective; based on senses
Inference
Subjective; based on perceptions
Qualitative Data
Data based on qualities
Quantitative data
Data based on quantities
Accuracy
The degree to which measurements agree with the accepted value
Precision
The degree to which measurements agree with one another
Percentage Error
Shows how far off a Measurment made in a lab is from the commonly accepted value
Percentage Error equation
|experimental value-accepted value| divided by accepted value times 100
Average
Sum of all numbers divided by the number of values
SI system
The system used by scientist around the world to make measurments
Length
Distance between 2 points
Unit= Meter/m
Mass
Amount of matter in an object
Unit=Kilogram/kg
Time
Interval between two events
Unit= seconds/s
Amount of substance
Unit=Mole/mol
Base units
Grams (g)
Seconds (s)
Litres (L)
Meters (m)
Temperature
Amount of heat in an object
Unit=Kelvin=k
Temperature conversions
k= C + 273.15
C= 5/9 (F-32)
F=(C*9/5)+32
Significant Figures= Sig figs
the number of digits in a measurment that reflect how accurate the measurement is
Not significant In Sig figs
placeholder zeros
ex. 0.006 the two zeros after the decimal
Significant in Sig figs:
Non zero numbers
123..
Sandwiched zeros
103
Trailing zeros WHEN DECIMAL IS PRESENT
0.1200 not 1200
When adding and subtracting Sig figs:
look at sigs only to the right of the decimal
When multiplying and dividing Sig figs:
look at all Sig figs
