You stir a spoonful of salt into a glass of warm water. The water looks clear. Where did the salt go?
AThe salt was destroyed by the water
BThe salt melted into a liquid
CThe salt dissolved — it broke into pieces too tiny to see and spread throughout the water
DThe salt sank to the bottom where you cannot see it
The salt dissolved. Its particles separated and spread evenly throughout the water, becoming too small to see. The salt is still there — you can taste it, and if you let the water evaporate, the salt will be left behind. Dissolving is not the same as melting or being destroyed.
Question 2 True / False
Most solid will dissolve in water if you stir long enough.
TTrue
FFalse
Answer: False
False. Many solids do not dissolve in water no matter how long you stir. Sand, rocks, plastic, and wood will not dissolve in water. Whether something dissolves depends on the properties of both the solute and the solvent, not on how long you stir.
Question 3 Short Answer
What is the difference between a solute and a solvent?
Think about your answer, then reveal below.
Model answer: The solute is the substance that gets dissolved (like sugar or salt), and the solvent is the substance that does the dissolving (like water). The solute breaks apart and spreads throughout the solvent to form a solution.
Think of the solvent as the host and the solute as the guest. Water is the most common solvent, but other liquids can be solvents too. The solute is always the material that seems to disappear into the solvent.