Central Board of Secondary Education (CBSE)
Sample Paper – 2012
Class – X
Chemical Equations and reactions
Very Short Answer (1 marks each)
Write the name and formula of compounds forms between
- Potassium and iodine ion .b.Sodium and sulphide ions . c. Aluminums and chloride ions
2. Milk sour when kept for a long time. What is reason behind it?
3. What will be when hydrogen combine with oxygen in presence of electric current/
4. What is electrolysis? Explain.
5. What do you mean by decomposition reaction? Give a suitable example
6. Calcium oxide react with water to form calcium oxide. Which type of reaction is it?
7. What will be when ferrous sulphate is heated?
8. What happen when copper metal is dipped in silver nitrate solution? Give the balance chemical equation?
9. Write chemical formula for following.
a. calcium fluoride.b.iron(II)bromide
10. Write chemical names of
a. Ag2O3 b.CuS c. Na2ZnO2
11. Why should a chemical equation be balanced?
12. Write formula of
a. Aluminums chloride b. Lead phosphate.
13. What is redox reaction? Give example with equation.
14What are oxidation and reduction reaction?
15. Why do gold and platinum not corrode in moist air?
Short Answers Type Question
1. Write balanced chemical equation for.
a. Zinc metal reacts with aqueous solution of hydrochloric acid to form zinc chloride solution and hydrogen gas.
b. Solid mercury (II) oxide is heated, liquid mercury and oxygen gas is produced.
c. Aqueous solution of sulphuric acid and sodium hydroxide react to form aqueous sodium sulphate and water.
2. Balance the following equation.
a. Fe(s)+CuSo4 (aq)—àFeSo4(aq)+Cu(s)
3. What is differences between decomposition and combination reaction? Explain with a suitable examples.
4. Can a displacement reaction be a redox reaction? Explain with examples.
5. Complete and balance
a. Cu+AgNO3–à ———————————
- Identified the substances oxidized and reduced.
2. What information’ do we get from a balanced chemical equations?
3. Classify the following as combination, decomposition, displacement and double displacement reaction.
c.2H2O sunlight 2H2+O2
4. What will be when zinc metal is dipped in copper sulphate solution? Give the chemical reaction involved. Explain which is more reactive, Zn or Cu.
5. What is the relationship between oxidizing and oxidation agent in a redox reaction? Illustrate with reaction in brief.