Answer:
Isotonic solutions have the same concentration of solutes as a reference solution, usually expressed as milliosmoles per liter (mOsm/L). Distilled water is a pure substance that does not contain any solutes, so it has an osmolarity of 0 mOsm/L. Therefore, compared to distilled water, most solutions are hypertonic, meaning that they have a higher concentration of solutes, or hypotonic, meaning that they have a lower concentration of solutes.
However, it is important to note that the term "isotonic" is often used to describe solutions that are similar in concentration to the fluids inside the human body. For example, saline solutions are often used in medical settings because they have an osmolarity similar to the fluids in the human body, making them isotonic in this context. In comparison to these solutions, distilled water is hypotonic.
So, to answer your question, it depends on the reference solution that is being used. Compared to distilled water, which has an osmolarity of 0 mOsm/L, most solutions are either hypertonic or hypotonic. However, compared to solutions that are similar in concentration to the fluids in the human body, distilled water is hypotonic.
Step-by-step explanation: