There are three perfect squares in a standard die; 1, 2, 4. If there is two standard dies, then the probability of getting a perfect square is 1/3 x 1/3 = 1/9. There are 4 numbers less than 5 in a standard die, making it 1/4 x 1/4=1/16.
Recrystallization is the process in which a compound is dissolved in a hot solvent and then allowed to cool which forms the crystals.
It is a technique used for purification of solids.
Recrystallization mainly depends on the solubility of the solvent that means the solid should be soluble in the solvent when it is hot and should be insoluble in the same solvent when it is cool.
The observations while doing recrystallization is to observe the purified crystals obtained and to filter it out.
2. B It is the outermost layer of Earth, composed of solid rock and divided into sections called plates. 3. B The inner core is kept solid by the intense pressure of all the layers above it.
