1. Types of water Czech Republic - MěVG Klobouky u Brna THE LAKES IN OUR LIVES 2014-2016

2. Hi, we are team from the Czech Republic. We would like to introduce our presentation about types of water. We hope that you will learn some new information about them.

3. Hardness of water - hard/light water -This water contains a huge amount of dissolved minerals (mostly of CaO = calcium oxide and MgO = magnesium oxide). -Hard water forms a limescale and affects the taste of drinking water. Drinking water About two-thirds of our planet are covered with water.Unfortunately, only 1% is usable for drinking. -Drinking water is treated water with well-defined standard ingredients which are added into the water. -In the 21st century in some parts of the world there is not good drinking water.

4. Groundwater -Groundwater is water located beneath the Earth's surface. The underground water accounts for 30% of all fresh water on Earth. -Groundwater contains a minimum of minerals and gases. Thermal water -Thermal water is special hot water that is enriched with mineral components. -Thermal water is approximately 30 ° C and it has therapeutic properties

5. Water chlorine -Water chlorine is used as a disinfectant of drinking water and water in swimming pools. -Chlorine is used as a disinfectant because it can destroy bacteria and viruses Addition of chlorine to water gives both hypochlorous acid and hydrochoric acid. -But concentrations of these acids in the water are always very low. Javel water - NaClO -Its name is also sodium hypochlorite. This compound of sodium, chlorine and oxygen is used as disinfectant of water and whitener of clothes. -It is always used in detergents.

6. Industrial water - Industrual water is from any factory. -It is very dangerous for nature. -It can be radioactive and is very often dirty. Lead water -It arises in heavy industry as a refuse from production -It is a very dangerous kind of water becouse the lead is poisonous. -Lead is one of the most frequent pollutants in the water.

7. Water of crystallisation -It is water inside of crystals. -It means a total weight of water in crystal substance. Hydrogen Peroxide -Hydrogen peroxide is a chemical compound with the formula H 2 O 2. -Hydrogen peroxide is often described as being "water but with one more oxygen atom.

8. Lime water -Pure limewater is clear and colourless, with a slight earthy smell and an alkaline bitter taste of calcium hydroxide. -It is a colourless liquid, slightly more sticky than water Aqua regia - HNO 3 +3 HCl -It is a mixture of nitrogen acid and hydrochlorid acid in ratio of 1:3. Aqua regia is very strong acid. It looks like yellowish-brown liquid. -It dissolves gold, platinum and other metal elements. -It is interesting that this liquid is named by water, but it hasn’t anything common with it.

9. Water with CaO and MgO Ground water Water under the surface Water from factories Water in swimming pools Water chlorine Hardeness of water Industrial water Test your knowledge