Amorphous substances show
(I) short and long range order
(II) short range order
(III) long range order
(IV) have no sharp `M.P`

Options

A. I & III
B. II & III
C. III & IV
D. II & IV

Answer

To solve the question regarding the properties of amorphous substances, we will analyze each option provided:

1. **Understanding Amorphous Substances**:
- Amorphous substances are solids that lack a well-defined long-range order in their atomic arrangement. They do not have a regular repeating pattern like crystalline solids.

2. **Evaluating Each Option**:
- **(I) Short and long range order**: This statement is incorrect. Amorphous substances only exhibit short-range order, meaning that while their immediate neighbors are arranged in a specific way, this arrangement does not extend over long distances.
- **(II) Short range order**: This statement is correct. Amorphous solids have a short-range order, which means that the arrangement of particles is consistent only over a small distance.
- **(III) Long range order**: This statement is incorrect. Amorphous substances do not have long-range order; their structure is disordered beyond the short range.
- **(IV) Have no sharp melting point**: This statement is correct. Amorphous solids do not melt at a specific temperature; instead, they soften and transition into a liquid state over a range of temperatures.

3. **Conclusion**:
- Based on the analysis, the correct properties of amorphous substances are:
- (II) Short range order
- (IV) Have no sharp melting point

Thus, the correct answer is option 2 and option 4.