1. Observations and Inferences
Prologue:
Observations and Inferences

2. Observations….
Things you can sense by
Sight
Touch
Smell
Hearing
Taste

3. Inferences are “guesses” based upon previous observations.
Tell whether each of the following is an observation or inferences….
“The stream is not polluted…
Inference
“The Earth is spherical”
Observation
“The earth’s outer core is liquid”.

4. Density = Mass/Volume Mass is…. The amount of matter in a sample
It is measured using a …
Triple beam balance (grams)
Volume is…
The amount of space a sample occupies
It is measured using a…
Graduated cylinder (cubic centimeters)

5. Calculate the density of a material which as a mass of 27
Calculate the density of a material which as a mass of 27.5 grams and a volume of 6.2 cc.
D= mass/volume
D = 27.5 g / 6.2 cc
D = 4.4 g/cc

6. % Deviation = (your answer - the accepted answer) / accepted answer
Calculate the % deviation if you calculated the density of a material to be 5.0 g/cc and in reality it is only 4.6 g/cc
First subtract to find the difference
= .4
Then divide that answer by the accepted value
.4 /4.6 =.087
Multiply by 100 to get the % = 8.7 %