Questions: Saturation: When No More Will Dissolve

Question 1

You keep adding salt to a cup of water and stirring. Eventually, salt starts sitting at the bottom no matter how much you stir. What has happened?

• A. The water is broken and can no longer dissolve salt
• B. The solution is saturated — the water is holding the maximum amount of salt it can
• C. You are stirring in the wrong direction
• D. The salt at the bottom is a different kind of salt that does not dissolve

Answer: (B)

The solution has reached saturation. Every solvent can only hold a certain amount of a given solute at a given temperature. Once that limit is reached, adding more solute just leaves it undissolved at the bottom. The water is not broken — it is simply full.

Question 2

Heating water allows you to dissolve more sugar in it.

• T. True
• F. False

Answer: True

True. For most solids like sugar and salt, warm water can dissolve more solute than cold water. The warmer water particles move faster and can pull apart more solute particles. This is why making sweet tea works better with hot water — you can dissolve much more sugar.

Question 3

What does it mean when a solution is saturated?

Model answer: A saturated solution is one that has dissolved the maximum amount of solute it can hold at that temperature. No more solute will dissolve — any extra will remain undissolved.

Saturation is the dissolving limit. It depends on the specific solute, the specific solvent, and the temperature. If you change any of these factors, the saturation point changes too.