HMH Unit 2.2 Day Two pgs 109-112

HMH Unit 2.2 Day Two

Pgs 109-112

Multiple Choice

Some objects that are ______ can bend without breaking.

• flexible

• magnets

• reflectivity

• hardness

Multiple Choice

Objects that are attracted to ______ are usually made of metal.

• flexible

• hardness

• magnets

• reflectivity

Multiple Choice

Mirrors and glass can be easily identified by the property of ______.

• flexible

• hardness

• magnets

• reflectivity

Multiple Choice

______ is a property that describes a brick wall.

• flexible

• hardness

• magnets

• reflectivity

Conductivity (Thermal and Electrical)

• You have already learned about several different properties that matter can have.

• Another one to add to the list is conductivity ability to move heat or electricity.

• Materials that let heat or electricity travel through them easily are conductive. Most things that are conductors are made of metal, although other materials can be conductive as well.

Conductivity (Thermal and Electrical)

• Materials that do not conduct heat or electricity are called insulators.

• Insulation is often made of cloth, plastic, or rubber. In fact have you ever noticed what covers the electric power cords of electric devices? The wires inside are covered with plastic to keep the electricity and heat form flowing out and starting a fire.

Open Ended

Why would holding up a metal umbrella during a lightning storm be a bad idea?

Multiple Choice

The spoon in the picture is made of _____.

• metal

• nylon

Multiple Choice

The spoon in the picture is made of metal and so it is a ____ conductor of heat and electricity.

• bad

• good

REMEMBER

Just looking at an object isn't a good way to determine its conductivity. Objects may be very polished so they look like metal but are actually made of another material. A way to test to see is by heating the item up, like in the pictures before this slide.

Dissolving and Evaporation

• Matter has so many different properties it is hard to keep track.

• Another property of matter you should consider is the ability to dissolve in water, called solubility.

• When something dissolves, it may look like one substance disappeared, but those particles are still there!

• They are just too small to be seen. For example, f you let salt water evaporate, you will be left with a pile of salt.

Dissolving and Evaporation

• Think back to the activity you did with the salt and the water. After you stirred the water with the salt in it, was the salt still there?

• You could not see it, but it was still in the water. it had dissolved.

•