Significant Figures
How many significant figures: 102,000
3
0.789 + 10
11
Write the following number in scientific notation:
2,300,000
2.3 x 106
What is the equation for density?
D= m/v
What are the units of density?
g/mL or g/cm3
How many significant figures
0.004700
125 x 2 =
300
True or false: The density of a mixture can never be changed
FALSE
What is the definition of density in words (not a math equation)
Oil floats on top of water, which is more dense?
Water
How many significant figures
100.0
4
0.479 + 0.2 =
0.7
An object has a density of 3.2 g/mL. Would this sink or float in water?
sink
A 45lb tree limb falls into a river and floats, a 20lb boulder sinks to the bottom of the river. Which is more dense?
the boulder
A 30cm3 block of gold weighs 105 grams. A 30 cm3 block of aluminum weighs 65 grams. Which substance is more dense
Gold
How many significant figures:
200
1
What is the rule for rounding after adding or subtracting numbers with different amounts of significant figures?
Round to the least amount of decimal places
True or false: Determining the density can be used to determine the identity of pure substances
True
True or false: 400mL of water is more dense than 4 mL of water
FALSE
mL is the unit of volume used for measuring liquids. What is the unit for volume of solids?
cm3
How many significant figures: 870
2
What is the rule for rounding after multiplying or dividing numbers with different amounts of significant figures
Round to the least amount of significant figures
examples: 1,234,567 0.07685432
7.000000
Which is more dense, 50 mL of salt water or 50mL of pure water? Why?
Salt water, more particles in a given space
What is the density of water?
1.00g/mL