Final answer:
The correct statement is that in the amorphous phase, the bonds connecting the SiO4 tetrahedral differ in length. Amorphous substances lack a long-range order and do not have a sharp melting point, unlike crystalline substances.
Step-by-step explanation:
When comparing an amorphous substance to a crystalline substance, one must consider the arrangement and bonding of particles within the substances. For instance, SiO4 tetrahedra in an amorphous phase, such as glass, do not exhibit a long-range order, whereas in a crystalline phase, like quartz, they have a definite and orderly arrangement.
To answer the student's question, the true statement among the options provided is: In the amorphous phase the bonds connecting the SiO4 tetrahedral differ in length. This is because the random network structure of an amorphous solid leads to varying bond lengths and angles. In contrast, statement 2 is false because in the amorphous phase, SiO4 tetrahedra do not bind in a definite and orderly manner, which is a characteristic of crystalline substances.
Statement 3 is also incorrect as the amorphous phase lacks long-range order by definition. Lastly, statement 4 is incorrect because it is the crystalline phase that has a sharp melting point due to the consistent forces between particles, while amorphous substances soften and melt over a range of temperatures.