Experimental Design
This is a factor in the experiment that is deliberately changed or manipulated by the scientist.
Independent Variable
True or False: A measurement can be precise but not accurate.
True
How many significant figures are in the number 0.00450?
3
How many milliliters are in 1 liter?
1000 milliliters
What is the first rule when solving dimensional analysis problems?
Write your given
What is the independent variable in an experiment where plant growth is measured with different amounts of water?
Amount of Water
Write this number using scientific notation: 67300000
6.73 x 107
When multiplying 2.34 by 6.7, how many significant figures should the answer have?
2
Convert 5 kilometers to meters.
5,000 meters
What is the rule for significant figures for dimensional analysis problems?
Go based off given!
What is the dependent variable in an experiment testing the effect of sunlight on plant height?
Plant Height
Does the following data have low precision or high precision?
1.00 g, 1.5 g, 2.0 g, 0.5 g
low precision
What is the correct way to round the number 3.987 to three significant figures?
3.99
If you have 250 milligrams, how many hectograms do you have?
0.00250
Convert 15 miles to kilometers using the conversion factor 1 mile = 1.609 kilometers. Answer needs to be in significant figures and units!
24 kilometers.
Identify the independent and dependent variables in an experiment where different fertilizers are tested to see which produces the most flowers on a plant.
Independent variable: Type of fertilizer.
Dependent variable: Number of flowers.
Multiply 3.2 x 105 by 4.5 x 103
need correct significant figures!!
1.4 x 109
Calculate the sum of 12.11, 0.023, and 3.5 using the correct number of significant figures.
15.6
Convert 0.75 liters to milliliters.
750 milliliters
How many centuries are in 8,760,000 minutes?
0.167 centuries
Explain why controlling variables is important in an experiment.
Controlling variables ensures that any observed changes in the dependent variable are due to the independent variable and not other factors.
A student measures the boiling point of water five times with a thermometer and gets the following data (in °C): 98.9°C, 100.2°C, 100.1°C, 99.9°C, 100.0°C. The accepted temperature 101.2°C.
What is the percent error for this data? AND is the student's data accurate, precise, neither or both?
accurate but not precise
Multiply 10.3 by 23.56. Then take your result and subtract is by 20. Answer needs to be written in the correct significant figures.
223
How many centimeters are in 2.5 meters?
250 centimeters
A student is performing an experiment to determine the density of copper coins. The student measures the mass of the coins and records the volume of water in a graduated cylinder before and after adding the coins. The data is shown below:
Mass of Coins: Initial Volume(mL): Final Volume(mL):
25.0 g 40.0 50.5
Determine the density of the copper coins.
2.38 g/mL