Page 42 - NCERT Science Class 10 English Medium
P. 42

3
                               CHAPTER


                               Metals and Non-metals











                   n Class IX you have learnt about various elements. You have seen
                 Ithat elements can be classified as metals or non-metals on the basis of
                 their properties.
                   n Think of some uses of metals and non-metals in your daily life.
                   n What properties did you think of while categorising elements
                      as metals or non-metals?
                   n How are these properties related to the uses of these elements?
                    Let us look at some of these properties in detail.

                 3.1
                 3.1
                 3.1 PHYSICAL PROPERTIES
                 3.1 PHYSICPHYSICAL PROPERTIESAL PROPERTIES
                 3.1 PHYSICAL PROPERTIESAL PROPERTIES
                      PHYSIC
                 3.1.1 Metals
                 The easiest way to start grouping substances is by comparing their
                 physical properties. Let us study this with the help of the following
                 activities. For performing Activities 3.1 to 3.6, collect the samples of
                 following metals – iron, copper, aluminium, magnesium, sodium, lead,
                 zinc and any other metal that is easily available.
                      Activity 3.13.1
                      Activity 3.1
                      Activity
                      Activity    3.1
                      Activity 3.1
                    n Take samples of   iron, copper, aluminium and magnesium. Note
                      the appearance of each sample.
                    n Clean the surface of each sample by rubbing them with sand paper
                      and note their appearance again.
                    Metals, in their pure state, have a shining surface. This property is
                 called metallic lustre.
                      Activity 3.23.2
                      Activity
                                  3.2
                      Activity
                      Activity 3.2
                      Activity 3.2
                   n Take small pieces of iron, copper, aluminium, and magnesium.
                      Try to cut these metals with a sharp knife and note your
                      observations.
                   n Hold a piece of sodium metal with a pair of tongs.
                      CAUTION:   Always handle sodium metal with care. Dry it by
                      pressing between the folds of a filter paper.
                   n Put it on a watch-glass and try to cut it with a knife.
                   n What do you observe?






                                                           2024-25
   37   38   39   40   41   42   43   44   45   46   47