Nature of Water

Capillarity: The rising of a liquid in a narrow tube, sometimes called capillary action.

capillarity: capillarity: (define in your own words) Draw your picture: Understanding Level

Colloid: A mixture that contains particles that are evenly distributed through a dispersing medium and do not settle out over time.

colloid: colloid: (define in your own words) Draw your picture: Understanding Level

Dissociation: The process by which the charged particles in an ionic solid separate from one another, primarily when going into solution.

dissociation: dissociation: (define in your own words) Draw your picture: Understanding Level

Hydrogen bonding: A connection between the hydrogen atoms on one molecule and a highly electronegative atom on another molecule, but not a full covalent bond.

Hydrogen bonding: Hydrogen bonding: (define in your own words) Draw your picture: Understanding Level

Osmosis: The flow of molecules through a selectively permeable membrane driven by concentration difference.

osmosis: osmosis: (define in your own words) Draw your picture: Understanding Level

Tyndall effect: The scattering effect caused when light passes through a colloid.

Tyndall effect: Tyndall effect: (define in your own words) Draw your picture: Understanding Level

Meniscus: A concave surface of a liquid resulting from surface tension. The bottom of the meniscus is used to measure the volume of a liquid in apparatus such as a graduated cylinder.

meniscus: meniscus: (define in your own words) Draw your picture: Understanding Level

Saturated solution: A solution that holds the maximum amount of solute under the given conditions.

saturated solution: saturated solution: (define in your own words) Draw your picture: Understanding Level

Supersaturated solution: A solution containing more solute than the usual maximum; they are unstable.

Supersaturated solution: Supersaturated solution: (define in your own words) Draw your picture: Understanding Level

Unsaturated solution: A solution in which the amount of solute dissolved is less than the maximum that could be dissolved.

Unsaturated solution: Unsaturated solution: (define in your own words) Draw your picture: Understanding Level

Solution: a mixture that is the same throughout, or Homogeneous

solution: solution: (define in your own words) Draw your picture: Understanding Level

Solute: the substance that is being dissolved when making a solution.

solute: solute: (define in your own words) Draw your picture: Understanding Level

Solvent: the substance that dissolves the solute when making a solution.

solvent: solvent: (define in your own words) Draw your picture: Understanding Level

Demo The Polar Nature of Water

In this apparatus, the seawater is an example of a _____. Jul'04 11th -18 A. strong electrolyte B. weak acid C. nonelectrolyte D. strong base

Which of the following objects will float on water? (Apr'04 10th -27) A B C D

A. Starch concentrations being equal on each side of the membrane B. Water passing from a region of lower starch concentration to one of higher starch concentration C. Water and starch volumes being the same D. Solute in the tubes changing from a higher temperature to a lower temperature Which would most likely cause the liquid in Tube A to rise?

Bathwater normally has electrolytic behaviors even though distilled water does not. This is because bathwater _____. Apr'04 11th -24 A. contains isotopes of hydrogen B. has been heated C. is separated into H+ and OH– ions D. contains dissolved minerals

Which factor makes water an effective solvent? A. The presence of molecular oxygen B. Its lack of covalent bonds C. The polar nature of its molecules D. Its abundance on Earth’s surface

The table shows times required for water to evaporate from identical containers. Which of these is the best question to ask before developing a reasonable hypothesis to explain the data? A. Why does a lower temperature slow the rate of evaporation? B. What is the boiling point of the water after both samples are heated? C. Why does water exist as a solid at -15C and as a liquid at 25C? D. How does the rate of evaporation change when a different container is used?

Which characteristic of water best explains its ability to dissolve a great variety of materials? Apr'06 11th -25 A. Its transparency in light B. Its electrical conductivity C. Its physical state of matter D. Its molecular arrangement

Power plants that discharge warm water into rivers have a negative effect on aquatic life. This is because the higher water temperature _____. Apr'06 11th - 21 A. increases the pressure of the river water B. increases the pH value of the river water C. decreases sediment solubility in the river water D. decreases the dissolved oxygen in the river water

The diagram on the right shows water molecules and ions from an NaCl crystal. What is the most likely reason that each water molecule is arranged so that the oxygen part of the molecule faces a sodium ion? A.The oxygen in a water molecule contains a partial negative charge. B.Gravity rotates the oxygen atoms to face the more-massive sodium ions. C.Hydrogen atoms create repulsive forces with chloride ions. D.Oxygen atoms form covalent bonds with sodium ions.

A student is working with four beakers that each contain a clear liquid. Which set of procedures would be best to use to determine whether one of the beakers contains only distilled water? Feb'06 11th -43 A. Observe odor Determine temperature Observe color Determine boiling point C. Observe volume Determine mass Observe color Determine pH B. Observe odor Determine pH Determine density Determine boiling point D. Determine mass Observe volume Determine temperature Observe odor

Fish survive through severe winters because of the property of water that allows water to _____. Apr'04 11th -26 A.form chemical bonds as it freezes, raising the water temperature below the ice B. increase in density while it freezes, dissolving more oxygen from the air C.expand when it freezes, creating a floating and insulating layer of ice D.precipitate vital nutrients when it freezes, increasing the food supply

A.The ratio of hydrogen to oxygen B.The ability to refract light C.The hydroxide ion concentration D.The freezing temperature What characteristic of water remains the same no matter what is dissolved in it?

Which of the following salts has the greatest solubility in water at 25C? A. CaCO 3 B. FeS C. HgCl 2 D. KClO 4

A.The density of water increases as temperature increases between 4C and 10C. B.The density of water decreases as temperature increases between 0C and 4C. C.The density of water decreases as temperature increases between 4C and 10C D.The density of water remains constant as temperature increases. 1.Which of the following statements best describes this relationship?

All of these can affect the rate at which a solid dissolves in water except____. Apr'03 11th -17 A. decreasing air pressure B. stirring the water C. increasing the temperature of the water D. using larger crystals of the solid

A.Thermal energy B.2.0 g of baking soda C.Ice cubes D.2.0 g of sodium chloride A recipe calls for 210 grams of sugar to be dissolved in 0.25 liter of water. After the mixture is stirred, some sugar crystals remain in the water. What can be added to the mixture to help dissolve the remaining sugar crystals?

The structure of pure water makes it a good ____. Fall'05 11th -36 A. solvent B. catalyst C. conductor D. nutrient

A recipe calls for 210 grams of sugar to be dissolved in 0.25 liter of water. After the mixture is stirred, some sugar crystals remain in the water. What can be added to the mixture to help dissolve the remaining sugar crystals?

Heat of solution: A measure of the amount of heat needed to raise the temperature of 1 gram of substance 1° C.

Heat of solution: Heat of solution: (define in your own words) Draw your picture: Understanding Level

Specific heat: The heat taken in or released in the dissolving process.

specific heat: specific heat: (define in your own words) Draw your picture: Understanding Level

Surface tension: The force needed to overcome intermolecular attractions and break through the surface of a liquid or spread the liquid out.

Surface tension: Surface tension: (define in your own words) Draw your picture: Understanding Level