Measurements
Precision/Accuracy
Density/Slope
Percent Calculations
Matter
100
What is the volume of the liquid in the cylinder?
6.61 mL
100
Is the following data PRECISE?
11.29 g, 11.47 g, 7.52 g, 10.99 g
Average: 10.32 g
Actual Value: 10.74 g
No! The measurements are not consistently similar to each other
100
How do we calculate density?
Mass / Volume
100
How do you calculate percent COMPOSITION?
Part / Whole x 100
100
What is the smallest unit of matter?
An atom
200
What is the mass of the object on the balance?
37.35 grams
200
Is the following data ACCURATE?
11.29 g, 11.47 g, 7.52 g, 10.99 g
Average: 10.32 g
Actual Value: 10.74 g
Yes! The average is close to the actual value
200
What is the density of an object if its mass is 12.0 g and volume is 15.3 mL?
0.78 g/mL
200
How do you calculate percent ERROR?
Estimated - Actual / Actual x100
200
What pure substance is formed from many of the same atoms?
An element
300
What is the volume of the liquid in the cylinder?
63.5 mL
300
When measurements are consistently close to each other or similar they are...
Precise
300
How do you calculate slope?
Y2 - Y1 / X2 - X1
300
What is the percent COMPOSITION for the candy in the trail mix?
Candy - 6 g
Trail Mix - 57 g
10.53 %
300
What pure substance is formed when atoms chemically bond together?
A compound
400
What is the rule we must follow when recording measurements in science?
Always estimate the last digit!
400
When measurements are close to the actual value they are...
Accurate
400
What is the slope of the graph with points at (3,12) and (9, 15)?
The slope is 0.5
400
What is the percent error if the actual value is 290 g and the estimated value is 240 g?
17.24 % error
400
What type of mixture is UNEVENLY mixed?
Examples - trail mix, Lucky Charms, LEGOS
A heterogeneous mixture
500
What is the volume of the METAL in the cylinder?
10 mL
500
Is the following data accurate, precise, or both?
9.52 g, 9.67 g, 8.98 g, 9.32 g, 9.41 g
Average: 9.38 g
Actual Value: 14.44 g
It is precise, but NOT accurate!
500
What does the slope of a mass vs. volume graph represent?
Density!
500
Will you have to memorize the equations for the test?
No! They will always be provided to you
500
What type of mixture is EVENLY mixed?
Examples - chocolate syrup, salt water, lemonade
A homogeneous mixture