Dissolving
What word means that a solid completely mixes into a liquid to form a solution?
Dissolving
What is a solution?
A mixture where a solute is completely dissolved in a solvent.
What variable do students usually change in a solubility experiment?
Temperature.
What method can separate a dissolved solid from a liquid?
Evaporation.
What does chromatography separate?
Mixtures of coloured substances.
What do we call the solid that dissolves in a liquid?
Solute.
What name is given to a solution that cannot dissolve any more solute?
Saturated solution.
What variable do they measure?
The amount of solute that dissolves
What method can separate an insoluble solid from a liquid?
Filtration.
Why must the baseline be drawn with pencil, not pen?
Because pen ink would dissolve and interfere with results.
What happens to the particles of a solute when it dissolves in a solvent?
They spread evenly between the solvent particles
What happens when you add more solute to a saturated solution? /
It does not dissolve; it settles at the bottom.
What should students keep the same to make it a fair test?
Amount of solvent, stirring, time.
A mixture of sand and salt water is made. How can we separate both substances?
Filter out sand, then evaporate the salt water.
What do we call the liquid that moves up the paper?
Solvent
Why does sugar dissolve faster in hot water than in cold water?
Because solubility increases with temperature.
How can you turn a saturated solution into an unsaturated one again?
By heating it or adding more solvent.
When the temperature of water increases, what usually happens to the solubility of most solids?
It increases.
A student filtered a mixture of copper sulfate (soluble solid) and calcium carbonate (insoluble solid),
What remains on the filter paper?
Calcium carbonate (insoluble solid)
In an ink test, one pen shows one colour spot and another shows three. What can you conclude?
One ink is pure, the other is a mixture.
Chalk does not dissolve in water. What word describes chalk?
Insoluble.
How can you make salt dissolve faster?
Stir, crush it, or heat the water
Why is repeating an experiment important?
To check for accuracy and reliability.
What equipment is needed for filtration?
Filter paper, funnel, beaker.
Explain why some colours travel further up the paper than others.
They are more soluble in the solvent.