01.
|
i |
ii |
iii |
iv |
v |
|
B |
C |
A |
A |
C |
02. (a) A
flame is a zone of burning gases that produces heat and light.
(b) The differences between luminous and
non-luminous flame (flames formed by the Bunsen burner)
|
LUMINOUS FLAME |
NON-LUMINOUS FLAME |
|
It is yellow in colour |
It is blue in colour |
|
It produces less heat |
It produces more heat |
|
It forms soot |
It does not form soot |
|
It burns quietly |
It burns with a roaring noise |
|
It has four zones |
It has three zones |
|
It has a wavy flame |
It has a triangular flame |
|
It is formed when air holes of the
Bunsen burner are closed |
It is formed when the air holes of the
Bunsen burner are opened |
03. Bunsen burner
04. (a) Uses
of a non-luminous flame
It
is used for:
§ Heating purposes (because it is very hot
i.e it produces more heat)
§ Flame test of certain chemical
substances
§ Welding purpose (because it is very hot
i.e it produces more heat)
§ Cooking (because it is very hot and it
does not form soot)
(b) Uses of luminous flame
§ Luminous flame is used mainly for
lighting because it is not very hot (it produces less heat). Some heat sources
that are used for lighting include candle, tin lamp (kibatari) and hurricane
lamp.
