Materials, Properties and Uses (Lesson 2)

 FOCUS QUESTION

What are some properties of common materials and their everyday uses?

SPECIFIC OBJS.

1.       Identify correct and safe ways of using, storing and disposing of materials and household items.

2.       Evaluate how the disposal of selected materials affects the environment.

CONTENT SUMMARY

Materials exist as solids, liquid or gases. Materials/objects have different properties, such as transparency absorbency, strength, magnetic property, and heat conductivity, which determine their everyday use.

Safety symbols, hazard symbols or safety labels are meaningful and recognizable graphical symbols that warn of or identify hazards associated with the location or item.

Improper disposal of some materials can affect the environment.

Materials can undergo reversible or irreversible changes. Irreversible changes cannot be undone and form new materials. Reversible changes can be undone. Reversible and irreversible changes can be useful in everyday life.

Substances can change their state by heating and cooling.  Melting, freezing, evaporation and condensation can cause materials to change state.

ENGAGE

Let's review past lesson by way of questioning. Can you name some hazardous materials and tell why they are so described.

Now do you think these materials should be disposed of as other garbage? Give reasons for your answers. Share your  responses with the groups for critique.

EXPLORE

We will watch this Youtube video clip to learn how  some materials (eg. Cell phones, plastics, batteries, etc ) may affect the environment.

Video: Hazardous waste disposal.

EXPLAIN

Present their gleaned information to the class, explaining the effects of improper disposal, ways to disposing of these waste. (Key points will be written on the chalkboard. Students will read information together, paying attention to proper pronunciation and inflectional endings).

EXTEND/ELABORATE

Create a dub poem to summarize the concepts learnt about improper disposal of hazardous waste and its effect.

You may include content material from the video clip below as well.

Video: disposing hazardous materials

EVALUATE

1.  Based on the picture below, which two (2) statements are likely effects that the improper disposal of the waste can have on the environment.

The hazardous materials can produce toxin which can harm the environment and human.   ¡

The activity can cause the growth of germs and bacteria .                                                      ¡

The garbage can be washed into the sea and make the habitat safe for marine lives.             ¡

The activity can add large amounts of carbon dioxide to the atmosphere.                              ¡

3 Tick the practices that are appropriate to manage garbage and save  our environment.

ü	PRACTICES
	Recycle, reuse
	Burning
	Burying
	Dumping in river

 4. Circle the list with the garbage that would be least harmful to the environment.

¡      plastic bottles,     soda cans,    plastic bags 

¡      paper bags,    vegetable leaves,      stale fruits

¡      batteries,     aerosol cans,        cell phones,   pesticides containers

Justify your answer. ______________________________________________________________________________

3.        5. Which of the sets below would be best to recycle in an effort to save the environment?

¡      plastic bottles,     soda cans,    plastic bags 

¡      paper bags,    vegetable leaves,      stale fruits

¡      batteries,     aerosol cans,        cell phones,   pesticides containers

Give reasons to support your answer. ______________________________________________