Separation Techniques and Mixtures

What is a mixture?

• A combination of two or more substances that change their original properties.

• A combination of two or more substances where all substances keep their original properties.

• A single substance that cannot be broken down.

• A liquid that has dissolved a solid.

Are mixtures usually easy or hard to separate?

• Always hard to separate.

• Usually easy to separate.

• Impossible to separate.

• Only separable by chemical reactions.

How can you separate iron filings from sand?

• By adding water.

• By using a magnet.

• By heating them up.

• By using a strainer.

What tool can be used to separate sand from gravel?

• A magnet.

• A water filter.

• A strainer.

• Tweezers.

What is the best way to separate different clothes mixed in a drawer?

• Use a water filter.

• Use a magnet.

• Use tweezers or your hands.

• Heat them up.

What happens in a solution?

• All substances keep their original properties.

• One substance dissolves into another.

• Substances are easily separated by hand.

• Substances are always visible.

When salt is mixed with water, what happens to the salt?

• It floats on top of the water.

• It sinks to the bottom and stays visible.

• It dissolves and seems to disappear.

• It changes into a new substance.

How can you separate the hot cocoa powder from the water after it has dissolved?

• By using a strainer.

• By cooling the solution.

• By heating the solution to evaporate the water.

• By adding more water.

If you have a mixture of sand, gravel, sugar, and water, which substances can be separated using a water filter first?

• Only the sugar.

• Only the water.

• The sand and gravel.

• The sugar and water.

What can make a substance dissolve faster in a liquid?

• Making the liquid colder.

• Letting it sit without stirring.

• Applying heat.

• Keeping the substance in large pieces.