Growing Crystals

More lockdown science! This time we've been growing crystals!

First up plain old sodium chloride. We boiled up some water and managed to dissolve 25 teaspoons of salt into roughly 300ml of water. We then poured it into this jar and suspended some string on paperclips

Why hot water? This is because more salt can dissolve in water when it's hot than cold. We created a saturated solution while hot, and as the water cooled it became supersaturated causing the salt to start crystallizing. The string acted to provide good sites for the crystals to grow.

After a few days a good number of crystals have grown on the string. We'll keep it for longer to see how they grow.

We also got a crystal set at Christmas. This contained a packet of potassium dihydrogen phosphate, a card tree and a marker pen.

The pen was used to colour the ends of the tree branches and the solution was placed in the dish at the bottom. As the solution was raised up the card by capillary action it reached the marker ink where it started crystallizing. It also took up the colour of the ink as the powder was initially white.

And the crystals seen through the microscope. The delicate nature of these is readily apparent.