The Saturation Puzzle

Investigation 2-3

Mixtures and Solutions

Mystery Substance?

• Was in kit with the salt and Epsom salts

• Might be salt or Epsom salt or something else

• Like to figure out what it is

• Need to wear protective goggles and be careful

Substance Data Sheet

• Has information about the properties of five substances, including salt and Epsom salts

• Observe the mystery substance and record properties on the Data Sheet

Challenge

• Can you test the mystery substance to find out what it is?

• @ 5 minutes to develop group plan for identifying the mystery substance.

• Once the planning time is up, begin your challenge

Mystery Material• What is the mystery substance?

• What evidence do you have to support your conclusion?

• Does this substance form crystals? How could we find out?

Solubility Results• Make sure you have the solubility

results for salt, Epsom salts, and the mystery chemical recorded in your notebook.

• Which of the three chemicals we tested is the most soluble in water?

• Which is the least soluble?• If you wanted to make 10 liters of

saturated salt solution to pickle some fish, about how much salt would you need?

Homework:

• Read Summary: Reaching Saturation and answer questions

• I-check 2

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?

• 45-65g of Epsom salts dissolves in 50ml of water

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?