Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Open MARKS Web Download App
Search any question & find its solution
Question: Answered & Verified by Expert
Assertion: The presence of a large number of Schottky defects in $\mathrm{NaCl}$ lowers its density.
Reason : In $\mathrm{NaCl}$, there are approximately $10^6$ Schottky pairs per $\mathrm{cm}^3$ at room temperature.
ChemistrySolid StateAIIMSAIIMS 2013
Options:
  • A If both assertion and reason are true and reason is the correct explanation of assertion.
  • B If both assertion and reason are true but reason is not the correct explanation of assertion.
  • C If assertion is true but reason is false.
  • D If both assertion and reason are false.
Solution:
2569 Upvotes Verified Answer
The correct answer is: If both assertion and reason are true but reason is not the correct explanation of assertion.
When an atom or an ion is missing from its normal lattice site, a lattice vacancy or defect is created, which is called Schottky defect. Due to missing density of crystal will be lowered.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.

Use on iOS or Desktop Download from Google Play