Page 139 - Science Class 6 Times Publication

into pieces by fast  owing rivers and streams, the gold particles are
released from the rocks. Thus, the free state of gold particles is found
in sands of the river banks. People can obtain small amount of gold
by washing the sand of river bank.

Gold is a yellow shining metal. So, it is used in making ornaments,

medals, statues, coins, etc. It is also used in lling teeth. Gold is a
very expensive metal

Main Points to Remember

1. The elements can be categorized into three types-metals,
metalloids and non-metals.
2. Metals are the elements which are hard, shiny and good
conductors of heat and electricity.

3. Non-metals are the elements which are not shiny and are
found in soft solid, gas or liquid state. They do not conduct
electricity.

4. The elements which show the properties common to both
metals and non-metals are called metalloids.
5. A homogeneous mixture of two or more metals or metals
and non-metals is known as alloy.
6. Iron, copper, silver, gold, etc are very useful metals.

Exercise

1. Choose the best alternative in each case:

a. A metal is
i. Malleable ii. Ductile

iii. Sonorous iv. All of these

b. The property of metal due to which it can be drawn into a thin
wire is called

i. Malleability ii. Ductility

iii. Conductivity iv. All of these

Times' Crucial Science and Environment 135 Book 6