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What does insoluble mean?
It means a solid cannot dissolve in a certain liquid.
Whats a reversible change?
A change that can be undone.
Water boiling is a/an ______ change
Reversible
How can you tell if a solid is soluble after adding it to a liquid? What should you look for?
If the liquid is clear and you cannot see any particles of the solid, then it is soluble.
Give an example of an irreversible change.
Examples: baking a cake, burning a candle...
A tin can rusting is a/an _______ change
Irreversible
What is a suspension?
A suspension is what forms when an insoluble substance is put in a liquid. The solid will either float or sink to the bottom.
Is cooking pasta a reversible or irreversible change?
Irreversible, you cannot unboil the raw noodles.
Is ocean water a pure substance or a mixture? Why?
Mixture of salt and water (and other things too probably)
What are the three ways to speed up the rate of dissolving?
Heat, stirring, small grain size.
Name 4 methods of separating mixtures
Colander, sieve, boiling, magnet, filtering, picking out with hands
I stir instant coffee into boiling water, and add some sugar. What are the solute(s) and what are the solvent(s)
Instant coffee and sugar are the solutes, and water is the solvent
What are the two parts of a solution called? Give an example of each.
Solute (any soluble solid) and solvent (any liquid).
Describe in steps how to separate a mixture of paper clips, sand, and water.
Use a magnet to get the paper clips out, then use a filter to trap sand while letting water drip out.
When I put one teaspoon of sugar in my tea, it dissolves, but if I add four more teaspoons it starts to sink to the bottom. Is sugar soluble in tea? Why or why not?
Yes, initially the sugar dissolved. When you add too much the water cannot absorb all of the solid. We say the tea is saturated with sugar!