undissolved

Everyday

Undissolved means not dissolved: still solid in a liquid, not mixed in so that it disappears. tree →

In the lessons

In science lessons on solutions and mixtures, pupils stir sugar or salt into water: if some sugar stays at the bottom, it is undissolved. A substance stays undissolved because the liquid is saturated (can't hold any more), or because the substance is insoluble, like sand. Undissolved solids can be separated by filtering. Phrases: «undissolved sugar», «undissolved solid».

Examples

• Some sugar was left undissolved at the bottom of the cup. tree →
• Sand stays undissolved in water. tree →
• Filter the mixture to remove the undissolved solid. tree →
• Stir longer if there are undissolved crystals. tree →
• Warm water leaves less salt undissolved. tree →
• The undissolved tablet sat in the glass. tree →
• Record how much stayed undissolved. tree →

Note

Prefix un- (not) + dissolved. «Dissolve» means mix into a liquid so you can't see it; dissolving is not melting — melting needs heat and no liquid. Mass is kept: dissolved sugar is still in the water.