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प्रश्न
A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
Are these changes chemical in nature?
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उत्तर
Yes, the changes are chemical changes because new substances iron sulphate (green) and copper (brown) are formed in the reaction.
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संबंधित प्रश्न
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Miscible liquids having slightly different boiling points can be separated by the
- evaporation
- distillation
- fractional distillation
- sedimentation
Fill in the blank
A change in which the substance can be brought back to its original state is called a _______ change.
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- Colour change
- Effervescence or gas evolved
- Evolution or absorption of heat
- Formation of a precipitate.
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Complete the table given below.
| Heat on iodine crystals | Colour of vapours evolved |
State the following reaction represent oxidation or reduction.
\[\ce{Cl- ->Cl}\]
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The percentage composition of Nitrogen in Ureas is ______.
Which of the following statement is incorrect for a chemical reaction?
Magnesium + oxygen → magnesium oxide.
2Mg + O2 → 2Mg O
