Formation of Crystals eTwinning project «More than STEM» Presentation and photos made by children of Science group in Balvi Primary school
Formation of Crystals
eTwinning project «More than STEM»
Presentation and photos made by children of
Science group in Balvi Primary school
Salt crystals
• Pour hot water into the cup till half. Add 2 tablespoons of cooking salt and stir until it is dissolved.
• Pour 2 tablespoons of made solution into a dish and place it in a warm place.
• Within a few days salt crystals are formed.
Why did it happen?
• Water evaporates. Evaporation occurs more quickly in a warm room.
• Once the water has evaporated, the salt crystals remain on the plate.
Crystals on the thread of yarn
• Fill 2 glasses with warm water. Add salt and stir it. When salt begins to stay on bottom of glass, stop adding salt to water.
• Cut the thread of yarn. Put it over glass, letting thread be in salt water.
• Crystals are formed slowly. It can take up to a week until a lot of small salt crystals are formed around the thread of yarn. In addition, the glass is also "grown" with crystals.
Small Salt Crystals
• Experiment secret: only a certain amount of salt can be dissolved in a given volume of water.
• If the water is the warmer, the more salt can dissolve.
• When the water slowly cools down, an "excess" salt begins to crystallize around the yarn's thread and edges of glass.
• You can also use food coloring.
Soda (sodium bicarbonate)
• Soda is a white, powdery substance.
• It is used in food industry as a dough cleanser.
• Drinking soda is great for removing various unpleasant smells.
• With soda you can clean sinks, tiles, taps.
Crystals on the yarn
• Fill 2 glasses with hot water. Mix in 6 teaspoons of soda and stir until it is dissolved.
• Put the glasses in a warm place.• Cut the thread of yarn and put
each end in glasses. The thread must stretch, but it should not touch the dish.
Crystals of Soda
• Within 1 week crystals appear on the thread.
• The crystals of soda look very beautiful.
• The thread absorbs the solution. When the water evaporates, the crystals of soda remain over.
• Crystals on the thread are formed when the solution begins to drip and evaporate from the yarn.