Properties of Water Worksheet KEY

Covalent tension solvent deposition dissolve polar viscosity condensation cohesion negatively surface adhesion cooler universal positively sublimation covalent 1. The hydrogen and oxygen atoms are held together by ___________________ bonds. polar 2. The electrons are not shared equally creating a ___________________ molecule. dissolve 3. The polarity of water allows it to __________________most substances. Because of this solvent universal it is referred to as the ______________________ _______________________. cohesion 4. Water molecules stick to other water molecules. This property is called______________. positively 5. Hydrogen bonds form between adjacent water molecules because the _______________ negatively charged hydrogen end of one water molecule attracts the _________________ charged oxygen end of another water molecule. 6. Water molecules stick to other materials due to its polar nature. This property is called adhesion __________________________. surface tension 7. __________________ _______________________ creates the skin-like surface formed due to the polar nature of water. viscosity 8. ____________________________ is the tendency for fluids to resist flow. cooler _______________________ water is more viscous than warmer water, allowing floating organisms to use less energy to keep from sinking. condensation 9. _______________________ is when water changes from a gas to a liquid. sublimation 10. _______________________ is when water changes from a solid directly to a gas. deposition 11. _______________________ is when water changes from a gas directly to a solid. 12. Why does ice float? water is less dense in solid form because hydrogen bonding between water molecules pushed molecules further apart into a set crystalline pattern 13. List the properties that ocean water has due to the fact that it contains salt. higher density conductivity decreased surface tension Life as we know it could not exist without water. All the chemical reactions of life occur in aqueous solution. Water molecules are polar and are capable of forming hydrogen bonds with other polar or charged molecules. As a result, water has the following properties: A. H20 molecules are cohesive; they form hydrogen bonds with each other. B. H2O molecules are adhesive; they form hydrogen bonds with polar surfaces. C. Water is a liquid at normal physiological (or body) temperatures. D. Water has a high specific heat. E. Water has a high heat of vaporization (energy needed to evaporate). F. Water’s greatest density occurs at 4°C. Explain how these properties of water are related to the phenomena described in parts a-h below. More than one property may be used to explain a given phenomenon. 14. During the winter, air temperature in the northern United States can remain below 0°C for months; however, the fish and other animals living in the lakes survive. D and F 15. Many substances – for example, salt (NaCl) and sucrose – dissolve quickly in water. B 16. When you pour water into a 25-ml graduated cylinder, a meniscus forms at the top of the water column. A and B 17. Sweating and the evaporation of sweat from the body surface help reduce a human’s body temperature. E and C 18. Water drops that fall on a surface tend to form rounded drops or beads. A 19. Water drops that fall on your car tend to bead up or round up more after you polish (or wax) that car than before you polished it. A 20. If you touch the edge of a paper towel to a drop of colored water, the water will move up into (or be absorbed by) the towel. B (and capillary action)