Consider the following statements regarding crystal defects:

1. In metals, a self-interstitial introduces relatively large distortions in the surrounding lattice because the atom is substantially larger than the interstitial position in which it is situated.

2. All crystalline solids do not contain vacancies and, it is possible to create such a material that is free of these defects.

3. Impurity point defects are found in solid solutions, of which there are two types: Substitutional and interstitial. 

Which of the above statements is/are correct?

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ESE Electronics Prelims 2021 Official Paper
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  1. 1 and 3 only
  2. 2 and 3 only
  3. 3 only
  4. 2 only

Answer (Detailed Solution Below)

Option 1 : 1 and 3 only
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ST 1: UPSC ESE (IES) Civil - Building Materials
20 Qs. 40 Marks 24 Mins

Detailed Solution

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Statement 2 is wrong because it is impossible to create a material free from deferts.

Statement 1 & 3 are correct.

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