It is exciting to run experiments and view changes in chemical structures of objects around. The crystal making process is another exciting experiment that high school students can practice in labs and learn more about science.
Like any other experiment, this experiment on crystal making with salts also requires some apparatus. The apparatus required for making crystals with salt is specified below:
A pair of scissors
Half a cup of salt
After observing for some time, the solution settles for a while and then salt crystals are formed along the strings. On observing more closely, students can see the difference between microbes that are present in them, their shape and colour, and how they are formed. The size of the crystal form will also differ such as small crystals and large single crystals. Many other observations can be made with a microscopic view of these crystals
The steps for preparing crystals from salts are specified below.
The first step is to heat the water of 120 ml in a pan until it starts bubbling.
The next step is to add Epsom or even alum for quicker results
The heated pan is taken off the heat and to which 60-120ml of salt is added.
Stirring the solution is important here so that the salt can dissolve and becomes a supersaturated solution.
Pouring this solution into a clean glass jar till the undissolved salt grains of the solutions also falls into the new jar.
The next step is to add food colour to the new jar.
Using a pencil, tie a string to it. The pencil has to remain balanced on top of the jar so that the string dangles easily into the water.
Once you put the jar into a safe place and wait for some time, you will observe the formation of crystals on the string submerged in the water.
[Image will be Uploaded Soon]
Follow the steps mentioned below to experiment on how to make crystals out of salt.
A container is required that is flat, shallow, and wide.
Distilled water along with alum salt or table salt is added to this container.
This solution is kept for rest for some time.
After some days, a thin layer of small crystals could be easily observed forming at the base of this solution.
Using a pair of tweezers, select a seed crystal after pouring out the liquid.
The next step involves attaching a smooth wire or fishing line to one side of the crystal.
Now make a new solution with the same salt that was used earlier.
This salt solution is then transferred into a clean jar where the seed crystal is placed very delicately without touching both and/or sides of the jar.
Cover this new jar with filter paper to protect it from dust. Do not use an airtight lid.
To remove impurities, keep pouring the solution through a filter paper every week.
After some weeks have passed by, you can take this newly formed crystal out and dry it. This crystal can further be protected by a layer of nail polish which prevents it from wearing off.
1. What is Salt?
In the terms of chemistry, salt can be defined as an ionic compound. It is made up of both cations and anions (positive charges and negative charges, respectively).
Acid + Salt → Salt + Water
NaOH + HCl → NaCl + H₂O
When a base compound such as NaOH reacts with the acid, that is, HCl then NaCl, which is salt and water are formed.
There are also different types of salts such as normal salts, acid salts, and basic salts. With the complete replacement of hydrogen atoms of an acid by a metallic ion or ammonium ion, normal salts are formed. Acid salts on the other hand are formed by partial replacement of hydrogen ions in an acid by a metal or ammonium ion. And lastly, basic salts are those that are formed by the partial replacement of the hydroxyl radical of a diacidic or triacidic base with an acid radical.
2. What is the Water of Crystallization?
The water of crystallization is defined as a fixed number of molecules of water that are present in one formula unit of a salt compound. The water of crystallization is called water of hydration or crystallization water and it is the water that is found in the crystalline framework of any salt or even metal complex. With the help of heating, these water crystals can be removed although the properties of the crystal may be completely lost in the process. Moreover, a salt that is associated with the process of water crystallization is also called hydrate. For example, in one formula unit of copper sulphate, there are five molecules of water and therefore the chemical formula for hydrated copper sulphate is CuSO₄.5h₂.