The document discusses videos that demonstrate the properties of hardness and metallic luster in metals. It asks discussion questions about whether sodium or iron can be cut, whether cut metals shine, and the names of these properties. It then defines hardness as a property of metals, states that sodium is a soft metal, and defines metallic luster as the shining appearance of newly cut metal surfaces. Finally, it lists various metals and asks the reader to arrange them into groups of hard and soft metals.

2. Click here for video

3. DISCUSSION POINTS
 WHAT DID YOU SEE IN THIS
VIDEO?
 COULD THE PERSON CUT THE
IRON?
 COULD THE PERSON CUT THE
SODIUM METAL PIECE?
 WHEN TRY TO CUT SODIUM,
IS SEEM TO BE SOFT OR HARD?
 WHAT ABOUT THE IRON PIECE?
 HERE SHOWS, WHICH PROPERTY OF
METAL??

4. CONSOLIDATION
HARDNESS IS YET ANOTHER
PROPERTY OF METALS.
SODIUM IS A SOFT METAL

5. Click here for video

6. DISCUSSION POINTS
 WHAT DID YOU OBSERVE?
 IS THE PIECE SHINES BEFORE CUTTING?
 IS THE METAL PIECE SHINES AFTER CUTTING?
 WHICH PART OF THE METAL SHINES?
 IS ALL METALS SHOW THIS PROPERTY?
 DO YOU KNOW THE NAME OF THIS?
 WHAT IS METALLIC LUSTURE?

7. CONSOLIDATION
THE SURFACE NEWLY FORMED
WHEN METALS ARE CUT,
HAS A SHINING APPEARANCE.
THIS PROPERTY IS KNOWN AS
METALLIC LUSTURE.

8. ARRANGE THE GIVEN METALS INTO HARD & SOFT
METALS
1. IRON
2. POTTASSIUM
3. SODIUM
4. CAESSIUM
5. TITANIUM
6. SILVER
7. ALUMINIUM
8. LITHIUM
9. GALLIUM
10.TUNGSTEN
11.PLATINUM
12.GOLD