Focus Question: Do different salts have different saturation

rates?

Investigation 2-2

Mixtures and Solutions

Solutions Up Close

• Explain what happens at the particle level when a solid dissolves in a liquid.

• How do you know when a solution is saturated?

• Sugar crystals aren’t very big when they stop growing. How could you make bigger sugar crystals?

Review Saturation Investigation

• What did we make?

• How did you find out how many grams of salt it took to saturate 50 ml of water?

Epsom Salts• The salt we put on food is one kind of

salt. There are hundreds of other kinds of salt in the world. The salt we will investigate today is call Epsom salts.

• Epsom salt is not used in food. It is used to make a soothing salt bath to soak sore feet. Don’t taste it, and don’t get it in your eyes or nose.

• What other kinds of salt have you heard of?

Epsom Salt Investigation• How can you find out if Epsom salts dissolves

in water to make a solution?• If it does dissolve, how can you find out how

much Epsom salts is needed to saturate 50 ml of water?

• How can we find out how many grams of Epsom salts it took to saturate 50 ml of water?

• Record results on your Saturating a Solution sheet - have Reporter add results to class board

Solubility• What conclusions can be made from the

results?

• An important property of a substance is how it dissolves in a liquid, such as water. The property of “dissolvability” is called solubility. Different salts have different solubilities.

• Were you able to dissolve more Kosher salt or Epsom salts in 50 ml of water?

Separating an Epsom Salt Solution

• How would you separate the Epsom salts in the saturated solution from the water?

• Set-up two evaporating dishes and labels to evaporate Epsom salt solution.

• Homework: Response Sheet - Reaching Saturation

• Read The Bends, page 20-24 and answer questions

Vocabulary• Solubility

– A property that substances have of dissolving or being dissolved easily. The greater the solubility of a substance, the more it dissolves.

• Epsom salts– A non-edible salt used to make a soothing

salt bath to soak sore feet.

Content

• Which is more soluble in water, salt or Epsom salt?

• Epsom salt is about four times more soluble than salt.

• Your questions?