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Calcium hydroxide and ammonium chloride when heated together will give an important ...

Calcium hydroxide and ammonium chloride when heated together will give an important product. This compound may be obtained dry by
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  • A Dissolving it in water, recrystallizing it and then drying in the oven
  • B Passing it through a concentrated aqueous solution of sodium hydroxide
  • C Passing it through calcium oxide
  • D Passing it through concentrated sulphuric acid
  • E Passing it through anhydrous calcium choride
Correct Answer: Option C
Explanation:
The correct answer is C: passing it through calcium oxide.

When calcium hydroxide (Ca(OH)₂) and ammonium chloride (NH₄Cl) are heated together, they undergo a reaction that produces ammonia (NH₃) gas and calcium chloride (CaCl₂). The reaction is:

\[ 2NH₄Cl + Ca(OH)₂ \rightarrow 2NH₃ + CaCl₂ + 2H₂O \]

To obtain the important product (ammonia gas) in a dry form, passing it through calcium oxide (CaO) is a suitable method. Calcium oxide, being a desiccant, will absorb moisture, thus drying the ammonia gas.

Thus, passing it through calcium oxide (which absorbs water) helps to obtain the ammonia gas in its dry form.

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