grade 8/ chemistry/ hydrogen/ worksheet

                             HYDROGEN

1.      Atomic number of hydrogen_______

2.      Which position does the hydrogen occupy in the periodic table

3.      Mention the electronic configuration of hydrogen

4.      The valency of hydrogen is ______

5.      Write the equation for the following-

a.       Potassium with cold water

b.      Calcium with cold water

c.       Aluminium with steam

6.      Name the reactant which results in the formation of triferric tetroxide

7.      Name the element which reacts very vigorously when treated with cold water

8.      Why is zinc treated with steam for the formation of hydrogen gas

9.      Write the molecular equation for the following-

a.       Lead and sodium hydroxide

b.      Zinc and sulphuric acid

c.       Aluminium and sodium hydroxide

d.      Magnesium and hydrochloric acid

10.  Why is nitric acid not used in the preparation of hydrogen

11.  Lead cant be used in the preparation of hydrogen.why

12.  What are the precautions to be taken while collecting the hydrogen gas

13.  What happens when zinc granules are treated with dilute hydrogen chloride

14.  Name the method used in the collection of hydrogen in lab method

15.  Draw a neat labelled diagram of the laboratory preparation of hydrogen

16.  How is hydrogen purified

17.  Name the drying agent used to remove moisture from the hydrogen

18.  Where is hydrogen liberated in the electrolysis of water

19.  Under what conditions is the water gas produced. Mention its constituents

20.  Give the reaction on how the hydrogen gas is liberated from water gas

21.  Name the catalysts used in the preparation of hydrogen through bosch process

22.  How are the following impurities removed- carbon dioxide and carbon monoxide from the bosch process

23.  How doe the hydrogen react when a burning splint is introduced in to the jar

24.  What happen when hydrogen is exposed to air

25.  Differentiate between oxidation and reduction

26.  What is redox reaction. Give an example

27.  Write the equation for the reaction between hydrogen sulphide and chlorine and mention the products which is under going oxidation and reduction

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