1. Welcome to The Mojave River Wildlands… Water Walk

2. Water Walk… Quiz-Time Let’s see what ya know… A Review of Water’s… Physical & Chemical Properties

3. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (1) Water contracts (gets smaller) when it freezes. False Water expands when it freezes and becomes less dense unlike most other sunstances.

4. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (2) Long legged bugs called “water striders” can skate along the surface of a body of water because: b.b. The hydrogen of one water molecule is attracted to the oxygen of another water molecule like opposite poles of a magnet are! The attraction is called a Hydrogen bond and the result is that water molecules demonstrate “cohesion” causing water to have a “strong surface” called “surface tension”.

5. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (3) Condensation is water coming out of the air. True When water vapor cools it takes up less space and contracts, allowing water molecules to stick to one another forming clouds and precipitation. Recent research has uncovered that most condensation starts on the surfaces of airborne bacteria!

6. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (4) More things can be dissolved in a strong acid than in water. False The movement of liquid water along with its ability to form hydrogen bonds, allows water to pull substances apart and dissolve them better but not always faster then an acids!

7. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (5) Rainwater is the purest form of water. False Precipitation of any kind (snow, rain, hail) contains dissolved minerals, gasses, acids, dust, pollen grains, viruses and microorganisms! Distilled water is the purest!

8. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (6) It takes more energy to heat cold water to 212 o F (100 o C) than it does to change “boiling” water at 212 o F (100 o C) to steam. False It takes 5x as much energy to turn boiling water into steam then it takes raise cool water to boiling point @ 212 o F. !

9. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (7) Water is the most common compound on Earth. True More then 70% of the earth is covered in water. 66% of our bodies are made of water.

10. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (8) Sea water is slightly more alkaline or basic (the pH value is higher) than most natural fresh water. True Neutral water (such as distilled water) has a pH of 7, which is in the middle of being acidic and alkaline. Seawater happens to be slightly alkaline (basic), with a pH of about 8. Most natural water has a pH of between 6-8, and acid rain can have a pH as low as 4.

11. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (9) Failing raindrops are tear-shaped. False A drop of water coming out of a faucet, does have a tear shape… until it can't hold on any more. But when it falls it look more like a small hamburger bun due to the interplay between gravity and surface tension. As a drops falls, the air below the drop pushes up from the bottom, causing the drop to flatten out somewhat.

12. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (10) Water boils & evaporates quicker at high altitude, than at the sea level. True At sea level water boils at 100 o C. At 2,400 m, water boils at 92 o C. This is because as the altitude gets higher, the lower air pressure makes it easier for the water molecules to break their bonds and attraction to each other and, thus, it boils more easily. or 202 o F @ 7,800 ft 212 o F

13. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (11) Water is the only substance that is found naturally on earth in three forms: liquid, gas, solid. True Water can commonly be seen in the solid, liquid and gaseous state on Earth.

14. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (12) Water can be compressed like air. False A water -filled syringe on a stand is loaded with weights to show the incompressibility of water.

15. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (13) Water is known as the universal ______________. c. solvent A substance that has the ability to dissolve both bases and acids, such as water is called a “universal solvent. Everything else dissolves in water as well... stone, iron, pots, pans, plates, sugar, salt, and coffee beans.

16. Water Walk… Quiz A Review of Water’s… Physical & Chemical Properties (14) The water we drink cannot be broken down or made. It has essentially stayed the same since the beginning of time, and has been used and reused by all life forms! True & False New water is being formed all the time. Dihydrogen Monoxide is also always being broken down into Hydrogen and Oxygen gas. However, most of the water cycling through the Earth and its living things stays the same, largely unchanged. At right, amino acids, the building blocks of protein, are being “digested” (top), requiring the breakdown of water, and being combined (bottom), creating water in the process! Condensation Rnx Hydrolysis Rnx