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How is sodium hydroxide formed?

Important Questions on Chemical Reactions and Equations

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Calcium oxide reacts vigorously with water to produce slaked lime.

CaOs+H2Ol →CaOH2aq

This reaction can be classified as:

(A) Combination reaction        (B) Exothermic reaction

(C) Endothermic reaction        (D) Oxidation reaction

Which of the following is the correct answer?

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What is observed when a pinch of sodium hydrogen carbonate is added to 2 mL of acetic acid taken in a test tube? Write the chemical equation for the reaction involved in this case. 
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When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution. The reaction is an example of a :

EASY
Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
On heating blue coloured powder of copper (II) nitrate in a boiling tube, black copper oxide, O2 and a brown gas X is formed.
(a) Identify the type of reaction and the gas X.
(b) Write balanced chemical equation of the reaction.
(c) Write the pH range of aqueous solution of the gas X.
HARD
Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions

In a double displacement reaction such as the reaction between sodium sulphate solution and barium chloride solution:

(A) exchange of atoms takes place.

(B) exchange of ions takes place.

(C) a precipitate is produced.

(D) an insoluble salt is produced.

The correct option is:

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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
The electrolysis of acidified water is an example of: 
HARD
Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
What would a student report nearly after 30 minutes of placing duly cleaned strips of aluminium, copper, iron and zinc in freshly prepared iron sulphate solution taken in four beakers?
HARD
Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
1 g of copper powder was taken in a China dish and heated. What change takes place on heating? When hydrogen gas is passed over this heated substance, a visible change is seen in it. Give the chemical equations of reactions, the name and the colour of the products formed in each case.
EASY
Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
What is observed when a solution of sodium sulphate is added to a solution of barium chloride taken in a test tube ? Write equation for the chemical reaction involved and name the type of reaction in this case.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
Decomposition reactions require energy either in the form of heat or light or electricity for breaking down the reactants. Write one equation each for decomposition reactions where energy is supplied in the form of heat, light, and electricity.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
The colour of NO2 and PbO formed when lead nitrate is heated are:
HARD
Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
Identify the substances that are oxidized and the substances that are reduced in the following reaction:
CuOs+H2g→Cus+H2Ol
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
A shiny brown coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black coloured compound formed.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
Explain reduction in terms of gain or loss of oxygen with two examples.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
Why is the amount of a gas collected in one of the test tubes in ‘Electrolysis of water’ activity double of the amount collected in the other? Name this gas.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
What does one mean by exothermic and endothermic reactions? Give examples.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions
State the observations you would make on adding sodium hydroxide to aqueous solution of ferrous sulphate.
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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions

What is the difference between the displacement and double displacement reactions? Write equations for these reactions.

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Science>Chemistry>Chemical Reactions and Equations>Types of Chemical Reactions

What is your observation in the following case:

Iron reacting with copper sulphate solution in water.