1.
Give
an example of an exothermic reaction.
2.
Write electronic configuration of an element having
atomic number 13
3.
“Oxidation
and reduction processes occur
simultaneously.” Justify this statement
with the help of an example.
4.
“Barium
chloride reacts with aluminium sulphate to give aluminium chloride and a precipitate of barium sulphate”
a. Translate the above
statement into a chemical equation.
b. State two types
in which this reaction can be classified.
5.
“A
solution of potassium chloride when mixed
with silver nitrate solution, an insoluble white substance is formed”.
a. Translate the above
statement into a chemical equation.
b. State two types for this reaction.
6.
Design
an activity to show a decomposition
reaction in which light is used to decompose a reactant. Write chemical
equation of the reaction and
state its one use.
7.
State the
reason why
(i)
an iron strip dipped in a blue
copper sulphate solution turns the blue solution pale green.
(ii) zinc is used in the galvanisation of iron and
not the copper.
8.
Why
do we store silver chloride in dark coloured bottles? Explain in brief.
9.
Draw
a labelled schematic diagram to show the electrolysis of water. Why is the amount of gas collected in one of the test tubes in this activity double of the amount collected in the other
?
10. What happens
when chlorine is passed over dry slaked time? Write chemical
equation of the reaction involved.
Mention three properties of the
product.
11. What is meant by skeletal equation ?
12. What is meant by thermal decomposition reaction
? Explain with
an example.
13. An aluminium can is used to store Ferrous sulphate solution. It is
observed that in few days holes appeared in the can. Explain
the observation and write chemical
equation to support your answer.
14. Give three
differences between displacement and
double displacement reaction.
15. If copper metal
is heated over a flame, it develops a coating. What
is the colour and composition of this coating ?
16. What change
will you observe if white
silver chloride is placed in sunlight ?
Write an equation for the
reaction and the type of the reaction.
17. What is Redox reaction ? Identify the substance oxidised and the substance reduced in the following
reactions :
(i) MnO2 + 4HCl →
MnCl2 +2H2O
+ Cl2
(ii) Cu0 +H2 → Cu
+H2O
18. What is the brown coloured gas evolved when lead
nitrate crystals are heated in a dry test tube ?
19. Write balanced equations for the reaction of :
(a) Iron
with steam
(b) Calcium with water.
20. On mixing solutions of lead nitrate and
potassium iodide in a test tube.
(a) Write
the chemical equation involved in
the balanced form.
(b) What
is the colour of the precipitate
? Name
the precipitate.
21. (a) Write
one equation each for
decomposition reaction when energy is supplied in the form of :
(i) heat (ii) light
(b) Account for the following.
(i) Paint
is applied on iron articles.
(ii) Oil and
fat containing food items are flushed
with nitrogen.
(iii) When
an iron nail
kept in copper sulphate solution, blue colour
of the solution fades and iron
nail becomes brownish.
OR
(a) What
do you mean by
(i) precipitation reaction (ii) exothermic reaction (iii) oxidation reaction
Write balanced chemical equation.
22. A solution of potassium chloride
when mixed with
silver nitrate solution, an
insoluble white substance is
formed. Write the chemical
reaction involved and also
mention the type of the chemical reaction ?
23. Why do we store silver
chloride in dark coloured
bottles ?
24. A magnesium ribbon is burnt in oxygen to give a white compound X accompanied by emission of light.
(a) Write the chemical
formulae of X
(b) Write a balanced chemical equation, when X is dissolved in water.
