Question

1. Is mixed state of two atomic species more stable than the separated state? a. Yes, always b. No, always c. It depends on materials 2. If two patterns are incommensurate, what will happen? a. Both patterns disappear b. Lower energy pattern prevails over the other one c. Higher energy pattern prevails over the other one 3. At absolute zero temperature (0 K), what kind of change in atomic arrangement will occur, naturally? a. Positive charge ions swap with negative charge ions b. Bigger atoms swap with smaller atoms c. Populous species atoms swap with deserted species atoms d. No change in atomic arrangement 4. At which temperature, will a synthesize material have more disorders? a. Higher temperature b. Lower temperature 5. At which cooling rate, will a synthesize material have more disorders? a. Higher temperature b. Lower temperature

Answer 1

1.

The stability of the species whether to bond or not depends on the material, ie if mixing gives stability, then two species with always mix and if mixing does not give stability it will not mix.

Example : oxygen exists in nature as O₂ (one O mixes with other O to form O₂ ) if oxygen does not mix in its case it will stay as[O] nascent oxygen which is unstable.

While as in other cases mixing is not required.

Hence option (c) is correct.