‘Matter’ MattersWhat is Matter?

Matter is anything that has

mass and

takes up space – volume

How do we measure matter?• Mass is a measure of the quantity of

matter (stuff) within an object.

• When you measure the mass on an object, you compare it to a standard unit. The unit for mass is ‘gram’.

• Is there a difference between mass and weight ?

So is it Mass or Weight ?

Weight is the force that gravity exerts on an objects’ mass.

What is gravity?

Gravity is the force that objects exert on each other because of their masses.

Mass and weight are closely related, but they are not the same. Weight is dependent on gravity, mass is not.

We use a spring scale to measure weight and the unit is called the newton.

How do we measure matter? Volume is the amount of space that an object occupies.

For a liquid, you use a graduated cylinder to measure volume. The units are ‘mL’. This is also the unit of volume for a gas. For a liquid and a gas, volume is the ‘capacity’ that its’ container can hold.

You can determine the volume of regular shaped solid by formula. (V = H x W x L) The units are cm3.

For measuring irregular shaped objects you can’t use a formula.

So…………what do you do?

8th Grade Science

This is called the displacement method. (two things cannot occupy the same space at the

same time)

8th Grade Science

The ‘meniscus’

“A characteristic of liquids in glass containers is that they curve at the edges. This curvature is called the meniscus. With water in glass, the meniscus will curve up at the edges and down in the center so we say you read the bottom of the meniscus."

mL vs. cm3

1 mL of a liquid occupies 1 cm3

Therefore, 1 mL = 1 cm3

And it has a mass of 1 gram.

Properties of MATTER

We’ve learned so far that matter has these properties:

• Mass• Volume• Weight

•Density

Density• Density is how compact the particles

are in an object.

More tightly packed particles make a denser substance.

Density

Density• Density is a measure of the amount of matter (mass) present

in a given volume of a substance.

• Density is a measure of how far apart or how close particles (atoms) are from one another in a substance; density is the mass per unit of space (volume).

• Density is normally expressed in units of grams per cubic centimeter (g/cm3) for a solid or (g/ml) for a liquid or gas. Therefore……

– Density is the mass in grams divided by the volume in cm3 or ml

– D = M ÷ V

• The density of a substance remains the same no matter how much or how little of the substance you have.

• Let’s do some examples and explain this……

Which one is more dense than the other ?

• Diet coke or regular coke

• Oil or water

• An ‘oak’ tree or a ‘pine’ tree

• Peanut butter or chocolate

• Fats or proteins

Density

Is an object dense because it is heavy or is it heavy because it is dense ?