Soaps and Salts
What are salts?
In chemistry, salts are ionic compounds that are formed from the neutralization reactions of an acid and a base. Salts have certain properties:
- Salts are made up of an equal number of anions (positive ions) and cations (negative ions)
- They are hard and brittle
- Most salts dissolve in water and are solids at room temperature
- They have strong bonds and a relatively high boiling point
- Salts are electrically neutral
- In their solid state, they arrange themselves in a rigid structure called a lattice
Salts come in a variety of tastes and colors. Some salts are not safe to eat.
Table Salt
What most people call "salt" is the chemical compound sodium chloride. It has the chemical formula NaCl. Sodium chloride dissolves in water and is what makes the ocean water salty.
Salt is necessary for animal life. It is also used to enhance the taste of our foods and to preserve foods.
Soap is a Salt
In chemistry, soap is a type of salt. This is because it is formed from the mixing of an acid and a base.
How does soap work?
Soaps and detergents help to clean clothes, skin, dirty dishes, and other items by dissolving grease. Detergents are made up of special molecules. Part of these molecules is attracted to water. The other part is attracted to grease. The part that is attracted to grease will dissolve the grease and break it up into smaller components that can then be rinsed away by water.
How is soap made?
Humans have made soap all the way back to the ancient civilizations of the Babylonians and the Egyptians. For many years soap was made from a mixture of ashes, animal fat, and water. Although we no longer make soap the same way, the chemistry for making modern soap is very similar.
Today soap is often made from a combination of fats and sodium hydroxide. As the soap is formed, the byproduct of glycerol is removed. Once the raw soap is produced, other ingredients like perfumes and colors can be added. The chemical process used to make soaps is called saponification.
Interesting Facts about Soaps and Salts
- Salts can be made by mixing an acid and a base or an acid and a metal.
- Thallium salt was once used as rat and ant poison.
- The green color of an emerald is because of small amounts of the salt chromium oxide.
- Around 250 million tons of salt was produced in 2010. Most of it is produced by the evaporation of ocean water and salt lakes.
- Glycerol, the byproduct of soap manufacturing, is used for making other chemical compounds such as plastics and explosives.
- Several different salts go into the manufacture of glass.
- Liquid soap was not invented until the late 1800s.
- Soap is a key ingredient in many lubricating greases.
Crystals
What are crystals?
Crystals are a special kind of solid material where the molecules fit together in a repeating pattern. This pattern causes the material to form all sorts of unique shapes.
Amethyst Crystal
How do they form?
The process of crystal forming is called crystallization. Crystals often form in nature when liquids cool and start to harden. Certain molecules in the liquid gather together as they attempt to become stable. They do this in a uniform and repeating pattern that forms the crystal.
In nature, crystals can form when liquid rock, called magma, cools. If it cools slowly, then crystals may form. Many valuable crystals such as diamonds, rubies, and emeralds form this way.
Another way crystals form is when water evaporates from a mixture. Salt crystals often form as salt water evaporates.
What unique properties do crystals have?
Crystals can have very flat surfaces called facets. They can form geometric shapes such as triangles, rectangles, and squares. The shapes are a direct result of the type of molecules and atoms that make up the crystal. Smaller crystals and larger crystals that were formed of the same molecules and in the same method should have similar shapes.
There are seven basic crystal shapes, also called lattices. They are Cubic, Trigonal, Triclinic, Orthorhombic, Hexagonal, Tetragonal, and Monoclinic.
Interesting Types of Crystals
Snowflakes - Snowflakes are ice crystals that are formed high in the clouds when water freezes. They always have six sides or arms, but every one of them is unique.
Timing crystals - When an electric current is sent through some crystals they vibrate at a very precise frequency. Quartz crystals are used in watches and other electronics to keep an accurate time.
Quartz - Quartz is a common mineral and crystal. It is one of the hardest common minerals. The gemstone amethyst is a purple type of quartz.
Diamonds - Diamonds are one of the most valuable minerals on Earth. Not only for jewelry, but diamond is also the hardest substance on earth and is used for special tools such as diamond saws. Diamond is a form of the element carbon.
Fun facts About Crystals
- Crystallography is the science of studying crystals and how they form.
- Some crystals, like diamonds, are really just one giant molecule made from lots of atoms of a single element.
- A lot of computer screens use liquid crystals for their display.
- They are very popular in jewelry because they can sparkle and come in many different colors.
- Some living organisms are able to produce crystals.
