What Is 'Every Solvent Can Dissolve Every Solute'? The Truth

The phrase “every solvent can dissolve every solute” is a common misconception. The truth is that solubility depends on the chemical properties of both the solvent and the solute, governed by the principle “like dissolves like.” A polar solvent like water will not dissolve a nonpolar substance like oil, and vice versa.

How Solubility Actually Works

Solubility is determined by the intermolecular forces between the solvent and solute molecules. Polar solvents (like water, ethanol, or acetone) have molecules with a positive and negative end, allowing them to dissolve other polar or ionic substances. Nonpolar solvents (like hexane, benzene, or turpentine) have evenly distributed electrical charges and can only dissolve nonpolar substances. This is why water and oil separate — water is polar, and oil is nonpolar.

A simple example: table salt (sodium chloride) is an ionic compound. It dissolves readily in water because the polar water molecules pull the sodium and chloride ions apart. However, salt does not dissolve in vegetable oil, a nonpolar solvent, because the oil molecules lack the charge to interact with the ions. Conversely, wax (a nonpolar hydrocarbon) dissolves in turpentine but not in water. The American Chemical Society explains that this selectivity is fundamental to chemistry and is used in everything from cleaning products to drug formulation.

There are also practical limits to how much solute a solvent can hold. Even when a solute is soluble, it has a saturation point — the maximum amount that can dissolve at a given temperature. For example, at room temperature, you can dissolve about 36 grams of salt in 100 milliliters of water. Add more, and it will simply sit at the bottom. Temperature often changes this limit: hot water can dissolve more sugar than cold water.

Key Takeaways

• “Like dissolves like” is the core rule: polar solvents dissolve polar/ionic solutes, and nonpolar solvents dissolve nonpolar solutes.
• No single solvent can dissolve every substance — the chemical compatibility between solvent and solute is always required.
• Solubility has a physical limit (saturation), and temperature can affect how much solute a solvent can hold.
• When choosing a solvent for a task (like cleaning or mixing), match the polarity of the solvent to the substance you want to dissolve.