solutes and solvents: what did the green tea say to the hot water? i solute you ! have you ever made...
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Solutes and Solvents:What did the green tea say to the hot water? I solute you!
Have you ever made ice tea? Often you can do so by mixing a powder with water. Did you use more water, or more powder?
Most likely, you used a lot of water, and a small amount of powder.
What kind of mixture is iced tea? It looks like a pure substance, but you know that it contains at least 2 components (water
and tea)
The part that is present in the larger quantity is called the solvent
The solute is present in smaller quantities
The solute s are the parts of a solution that dissolve; solutions
are generally made by dissolving one or more solutes in a solvent
Liquid Solutions
You are probably familiar with a variety of liquid solutions. These all have a liquid solvent. Lets create a list of liquid solutions:
In food preparation, the solvents are usually liquids like water, vegetable oil, or an alcohol (like vanilla extract)
In ice tea, water is the solvent
Water is the most common solvent on Earth
Although water is the most common solvent on Earth, it doesn’t dissolve everything: other solvents are needed for specific things: Ethanol is used as a solvent for perfumes
Turpentine is used as a solvent for paints
Ethyl acetate is one of the solvents used in nail polish
Liquid Solutions cont…
Solutes that dissolve in liquids may be solid, liquids or gases. Salt and sugar are common solid solutes Acetic acid is a liquid solute added to water, to form vinegar Gases like carbon dioxide and nitrogen dissolve in our blood and are carried
around our bodies What other solids, liquids and gases (solutes) act as solutes that dissolve
in liquids
Water: The Universal Solvent
Tap water generally looks and tastes like pure water, yet it is a solution that contains many, many solutes. These include:
Iron
Aluminum
Salt
Fluorine
Calcium
Magnesium
Chlorine
How did they get into your tap water.
Water: The Universal Solvent cont…
As water flows in rivers and lakes and underground, it comes into contact with soil, gases and minerals (eg. Gases from the air and minerals from the rock and soil dissolve in water)
Pollutants may also dissolve in the water
Before reaching your tap, it is cleaned to make it safe for drinking; chlorine and fluorine are sometimes added to the water
Chlorine kills bacteria and fluorine may help keep your teeth healthy
Water probably dissolves more different substances than any
other solvent
For this reason, WATER is the Universal Solvent
Water is the Universal Solvent
Water is important to every living thing on earth. Being the Universal Solvent means that wherever water goes, either through the ground or through our bodies, it takes along valuable chemicals, minerals, and nutrients.
It is water's chemical composition and physical attributes that make it such an excellent solvent. Water molecules have a polar arrangement of the oxygen and hydrogen atoms—one side (hydrogen) has a positive electrical charge and the other side (oxygen) had a negative charge. This allows the water molecule to become attracted to many other different types of molecules.
Water can become so heavily attracted to a different molecule, like salt (NaCl), that it can disrupt the attractive forces that hold the sodium and chloride in the salt molecule together and, thus, dissolve it.
Source: http://water.usgs.gov/edu/qa-solvent.html
Solid Solutions
Not all solutions are liquids. In a solid solution, both the solvent and the solute
are solid. The gold used to make jewellery is often called 14-karat gold.
Pure gold is actually 24-karat, so 14-karat gold is made up of 14 parts gold to 10 parts of other metals – generally copper, silver, nickel or palladium
Gold is the solvent and the other metals are the solutes
Solid solutions are called alloys when they contain two or more metals: to make alloys, metals are heated until they melt, and then they are mixed together, and allowed to cool.
Brass is an alloy of copper and zinc; bronze is an alloy of copper and tin
With both brass and bronze, copper is the solvent. What are the solutes.
Gas Solutions
The air you breathe is 71% nitrogen gas, 21% oxygen gas and 1% argon gas, along with smaller amounts of other gases like carbon dioxide.
Air is, therefore, a solution that is also a gas.
What is the solvent for the air we breathe. What are the solutes.
Water Pollution
Plants and animals get some of the nutrients they need from water.
Unfortunately, because water is such a good solvent, it can also dissolve pollutants, too.
Pollution includes any pure substance or mixture that contaminates the natural environment
Polluted water is a mixture of pure water and pollutants
It is crucial to keep water in our lakes, rivers and oceans clean, so that organisms can grow and live there normally