Which of the following statements is(are)true for precipitate particle size?
I Particle size must be large enough to not clog or pass through a filter.
II Particle size is controlled by precipitation conditions.
III Thermodynamics favors larger crystals because the surface atoms have higher energy than internal atoms and the fraction of atoms on the surface is smaller for larger crystals than smaller crystals.
IV Ostwald ripening is the process where smaller particles re-dissolve and larger crystals grow.
A)III only
B)I,II,and IV
C)II and IV
D)I,II,III,and IV
E)II,III,and IV

Question

Quizplus · Accepted Answer

All statements are true regarding precipitate particle size. Statement I is practical in nature, ensuring that particles are of a size that can be effectively filtered. Statement II highlights the influence of precipitation conditions (like concentration, temperature, and presence of additives) on particle size. Statement III explains the thermodynamic preference for larger crystals due to lower surface energy per atom. Statement IV describes Ostwald ripening, a process that leads to the growth of larger particles at the expense of smaller ones, further influencing the size distribution of precipitates.

Which of the Following Statements Is(are)true for Precipitate Particle Size