a look at density and how to calculate it. the ratio of the mass of a substance to the space it...

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Density A Look at Density and How to Calculate It

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Page 1: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Density

A Look at Density and How to Calculate It

Page 2: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Definition of DENSITY: The RATIO of the mass of a substance to

the space it takes up (volume)

Substances have a characteristic density

Determined by how compact the atoms are inside

Page 3: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

The maximum density of MOST materials occurs in the SOLID phase…

solids have high densitiesgases have low densities

Page 4: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic
Page 5: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Can you think of an exception to this rule?

Page 6: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic
Page 7: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

What happens to the molecules in liquid water as water freezes?

Page 8: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Molecules move farther apart and EXPAND!

Ice (solid water) is LESS dense than liquid water

It floats in liquid water!

Page 9: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Will it Float? Density can

predict if something will float.

How?

Page 10: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Will it Float? The density of

liquid water is 1 g/mL.

Objects with a HIGHER density than water will ________.

Think of some examples…

Page 11: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

It Floats If it has LOWER

density, it will ________.

Think of some examples…

Page 12: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Other factors that affect DENSITY:

The density of a GAS varies with pressure and temperature:• Higher temperature – molecules farther

apart – LESS dense• Lower temperature – molecules closer

together – higher pressure - MORE dense

Page 13: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic
Page 14: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic

Units for Density Just like length, volume and mass,

density has to be labeled with the correct unit…

g/cm³ or g/mL is the standard unit for density. 1cm³ = 1mL

Page 15: A Look at Density and How to Calculate It.  The RATIO of the mass of a substance to the space it takes up (volume)  Substances have a characteristic