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In which one of the following situations chemical reaction does not occur?
- a)Common salt is exposed to air
- b)Coal is burnt in air
- c)Sodium is placed in water
- d)Iron is kept in moist air
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
In which one of the following situations chemical reaction does not oc...
When common salt (sodium chloride) is exposed to air, no chemical reaction occurs under normal conditions because there is no change in its chemical composition. The exposure to air does not alter the chemical structure of common salt, hence no chemical reaction takes place. In contrast, burning coal in air, placing sodium in water, and keeping iron in moist air all result in chemical reactions due to changes in chemical composition.
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In which one of the following situations chemical reaction does not oc...
Understanding the Chemical Reactions
Chemical reactions involve the transformation of substances, where reactants are converted into products. Let's analyze each option to determine where a chemical reaction does not occur.
Option A: Common Salt Exposed to Air
- When common salt (sodium chloride) is exposed to air, it remains chemically unchanged.
- It does not react with the components of air (like oxygen or carbon dioxide) under normal conditions.
- Therefore, no new substances are formed, and no chemical reaction takes place.
Option B: Coal is Burnt in Air
- Burning coal is a combustion reaction where coal reacts with oxygen.
- This process produces carbon dioxide, water, and other compounds.
- Hence, a chemical reaction occurs.
Option C: Sodium is Placed in Water
- Sodium reacts vigorously with water, producing sodium hydroxide and hydrogen gas.
- This reaction is highly exothermic and is a classic example of a chemical reaction.
Option D: Iron is Kept in Moist Air
- When iron is exposed to moist air, it undergoes oxidation, leading to the formation of rust (iron oxide).
- This is a chemical change as new substances are formed.
Conclusion
Among the options, only option A (common salt exposed to air) does not involve a chemical reaction. The other options all result in chemical changes, producing new substances. Understanding these reactions helps in recognizing the stability of certain compounds in different environments.
Chemical reactions involve the transformation of substances, where reactants are converted into products. Let's analyze each option to determine where a chemical reaction does not occur.
Option A: Common Salt Exposed to Air
- When common salt (sodium chloride) is exposed to air, it remains chemically unchanged.
- It does not react with the components of air (like oxygen or carbon dioxide) under normal conditions.
- Therefore, no new substances are formed, and no chemical reaction takes place.
Option B: Coal is Burnt in Air
- Burning coal is a combustion reaction where coal reacts with oxygen.
- This process produces carbon dioxide, water, and other compounds.
- Hence, a chemical reaction occurs.
Option C: Sodium is Placed in Water
- Sodium reacts vigorously with water, producing sodium hydroxide and hydrogen gas.
- This reaction is highly exothermic and is a classic example of a chemical reaction.
Option D: Iron is Kept in Moist Air
- When iron is exposed to moist air, it undergoes oxidation, leading to the formation of rust (iron oxide).
- This is a chemical change as new substances are formed.
Conclusion
Among the options, only option A (common salt exposed to air) does not involve a chemical reaction. The other options all result in chemical changes, producing new substances. Understanding these reactions helps in recognizing the stability of certain compounds in different environments.
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In which one of the following situations chemical reaction does not occur?a)Common salt is exposed to airb)Coal is burnt in airc)Sodium is placed in waterd)Iron is kept in moist airCorrect answer is option 'A'. Can you explain this answer?
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