ICSE Worksheet for Chapter - 7 Oxygen Class 8

Worksheets For class 8

Find ICSE  Worksheet for chapter-7 Oxygen class 8

1. CLASS-8
2. BOARD: ICSE
3. Chemistry Worksheet - 7
4. TOPIC: Oxygen
5. For other ICSE Worksheet for class 8 Science check out main page of Physics Wallah.

SUMMARY-

• Discovery of oxygen.
• Preparation –
• Laboratory method from H₂O₂ and KClO₃.
• Industrial method from air and water.
• Physical and chemical properties, test and uses.

SECTION -1

1. Fill in the blanks :
   1. Oxygen is ___________ gas which _____________combustion.
   2. Galvanizing is the process of coating iron with ________to prevent it from rusting.
   3. Burning is a ________oxidation process in which ______________are evolved.
   4. Carbogen is a mixture of 95% ____________and 5%_____________.
   5. The boiling point of liquid oxygen is __________.
   6. The process of prevention of rusting by coating of silicates baked on iron is called ____________.
2. What is the colour of the flame obtained when following metals are heated in presence of oxygen :-
   1. Sodium
   2. Calcium
   3. Magnesium
   4. Iron
3. Write balanced equations for the action of oxygen on the following:
   1. Phosphorus
   2. Iron
   3. Sodium

SECTION-2

1. Give equations for the preparation of oxygen on thermal decomposition of :
   1. Red lead
   2. Lead dioxide
   3. Mercuric oxide
2. Why these methods are not preferred for laboratory preparation of oxygen?
3. How oxygen was discovered from red mercuric oxide ?
4. Differentiate between burning and respiration.
5. Give two chemical tests for the detection of oxygen gas.
6. Show that the catalyst MnO₂ does not undergo any change in mass or chemically on heating with potassium chlorate in the laboratory preparation of oxygen.
7. Describe how oxygen can be manufactured by electrolysis of acidified water.
8. How welders and steel plants use oxygen for welding and cutting of metals ?