Final answer:
Non-electrolytes are covalent or molecular substances that do not produce ions when dissolved in water, unlike electrolytes, which do yield ions and conduct electricity.
Step-by-step explanation:
Non-electrolytes are typically covalent or molecular substances that dissolve in water as molecules instead of ions. Examples include methanol, acetone, sugar, and glucose, which remain neutral molecules when dissolved and do not conduct electricity. In contrast, electrolytes are substances that dissolve in water to yield ions. These can be strong electrolytes, like soluble ionic compounds and strong acids that ionize completely, or weak electrolytes, like weak acids and bases that ionize to a lesser extent. Understanding the difference between electrolytes and non-electrolytes is important for predicting solubility and electrical conductivity in solutions.