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प्रश्न
What is a redox reaction? Explain with an example.
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उत्तर
A redox reaction is a reaction in which oxidation and reduction reactions take place simultaneously.
When copper oxide is heated with hydrogen, then copper metal and water are formed:
In this reaction, CuO is changing into Cu. That is, oxygen is being removed from copper oxide. Oxygen is being added to hydrogen; H2 is changing into H2O. This shows that oxidation and reduction occur together.
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संबंधित प्रश्न
Taking into consideration the relationship in the first pair, complete the second pair
2H2 + O2 → 2H2O :Combination Reaction :: 2HgO → 2Hg + O2:_________
State an important use of decomposition reactions.
What type of chemical reaction is represented by the following equation?
\[\ce{X -> Y + Z}\]
Name the product formed on strongly heating ferrous sulphate crystals. What type of chemical reaction occurs in this change?
A metal salt MX when exposed to light splits up to form metal M and a gas X2. Metal M is used in making ornaments whereas gas X2 is used in making bleaching powder. The salt MX is itself used in black and white photography.
(a) What do you think metal M is?
(b) What could be gas X2?
(c) Name the metal salt MX.
(d) Name any two salt solutions which on mixing together can produce a precipitate of salt MX.
(e) What type of chemical reaction takes place when salt MX is exposed to light? Write the equation of the reaction?
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
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- reactants
- water
- wind
- heat
What are thermal decomposition reactions ? Explain with an example.
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b) When we pass this gas through limewater what change, did you observe?
c) Write down the chemical reaction showing the product formation after heating the Calcium carbonate.
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- Direct combination
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Photolysis is a decomposition reaction caused by ______
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Balance the following chemical equation and identify the type of chemical reaction.
`"H"_2"O"_2("l") overset("U V")(->) "H"_2"O"("l") + "O"_2("g")`
- Identify the gasses evolved at the anode and cathode in the above experimental set up.
- Name the process that occurs. Why is it called so?
- Illustrate the reaction of the process with the help of a chemical equation.
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