Salt Crystals

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Crystallization

    I have emphasized this concept in many of my previous blogs, but the impact that visuals or models have on a student's learning is amazing. Especially in units that require looking at photos of certain things to understand... why not have the student create the visual themselves?  

    An area where this would apply would be our current unit about minerals and crystals. Whether in class or at home, a student would be able to complete this lab fairly easily. The easiest of all recipes would be that of a salt crystal. Here is an example of a salt crystal recipe:

What You’ll Need

To grow your own salt crystals you’ll need:

  • Table salt – sodium chloride
  • Distilled Water
  • A clean, clear glass container – a jam jar is perfect
  • String
  • A spoon for stirring.

What To Do

Here’s what to do:

  1. Stir salt into boiling hot water until no more salt will dissolve (crystals start to appear at the bottom of the container). Be sure the water is as close to boiling as possible.
  2. Carefully pour the solution into your jar. (putting a spoon into the jar before adding the water should prevent the jar breaking.
  3. Suspend your string into the jar from the spoon laid across the top of the jar.
  4. Leave your jar somewhere it will not be disturbed and wait for your crystal to grow!

This particular recipe also lists some questions to conclude the lab, as shown below.

What To Look For

Once your crystals have grown, here are some things for you to look for in them:

  • Any impurities in the salt or the water will change the shape and colour of the crystals you grow. What shape and colour are yours?
  • Try using different types of table salt – try iodized salt, un-iodized salt, sea salt, or even salt substitutes. Is any difference in the appearance of the crystals?
  • Try using different types of water, such as tap water compared with distilled water. Is there any difference in the appearance of the crystals?

Source: https://www.saltassociation.co.uk/education/properties-of-salt/grow-salt-crystal/



Salt Crystals

While a salt crystal is arguably the easiest crystal to make, there are certainly others that can be made by a student in lab as well. Here are some other examples:


Sugar Crystals


Borax Crystals


Copper Sulfate Crystals

* All of the recipes for these can be found on: https://interestingengineering.com/nine-beautiful-crystals-you-can-grow-at-home

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