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प्रश्न
Explain the following reaction with one suitable example of Displacement reaction.
उत्तर
Displacement reaction: In this reaction a more reactive element displaces a less reactive element from its compound, e.g. Reaction of iron with copper sulphate.
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संबंधित प्रश्न
Give one example that illustrates the following characteristics of a chemical reaction:
Change in state
Give reason .
A person suffering from acidity is advised to take an antacid.
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Reduction is a chemical reaction in which there is
- removal of hydrogen
- removal of oxygen
- addition of oxygen
- none of these
FILL IN THE BLANK
In a double decomposition precipitation reaction both the reactants must be ............ soluble.
FILL IN THE BLANK
........... electrolytes dissociate completely in aqueous state and allow large amount of electricity to flow through it.
What are biocatalysts ?
Fill in the blank:
The substances formed as a result of a chemical reaction are called _______
Write true or false :
Hydrogen sulphide has rotten egg smell .
A chemical equation is a statement that describes a chemical change in terms of
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
The spoiling of food is a chemical change which is recognized from the generation of certain ______ due to it.
Choose the correct option from the bracket and explain the statement giving a reason.
(Oxidation, displacement, electrolysis, reduction, zinc, copper, double displacement, decomposition)
Addition of an aqueous solution of ZnSO4 to an aqueous solution of BaCl2 is an example of ______ reaction.
Give reason for the following:
Blue solution of copper sulphate changes to green when a piece of iron is added to this solution.
Multiple choice:
Thermal decomposition of sodium carbonate will produce
What do you understand by 'chemical reaction'?
What is observed in performing the following :
| Hydrogen | Oxygen | Carbon dioxide | Chlorine | |
| Litmus test | ||||
| Apply a burning splint to the gas | ||||
| Colour of gas | colourless | colourless | colourless | greenish-yellow |
| Odour of gas |
State the original colour of the following substance and colour of residue obtained after heating.
Copper carbonate
What do you observe when dilute sulphuric acid is added to the following:
Sodium Sulphide
Distinguish by dilute sulphuric acid.
Sodium sulphide and sodium sulphite?
Select the correct answer for the following options:
The basic gas obtained when two gases react in presence of a catalyst and the reaction is exothermic.
Select the correct answer for the following options:
The pale blue precipitated obtained when copper [II] sulphate reacts with sodium hydroxide.
Give reason for the following:
Electrolytic decomposition of water is a reaction involving change of state.
Give balanced equation for the following conversion affected by heat alone on the substance:
Hydrated copper sulphate to sulphur dioxide
Give balanced equation for the following conversion affected by heat alone on the substance:
Zinc carbonate to zinc oxide
Analogy:
H2O: Water:: NaCl: ______.
Write some materials prepared by chemical changes.
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.
Do you think the formation of rust from iron is a chemical change?
How would you show that the settling of curd is a chemical change?
Write the characteristics of chemical change.
The reaction of H2 gas with oxygen gas to form water is an example of ______.
Both CO2 and H2 gases are ______.
