Water Properties Chapter 3

Questions and Answers

Water is made up of ___ atom of oxygen and _ atoms of ________.

one; two; hydrogen

Water molecules are _ which gives the end bearing the oxygen atom a slightly charge and the hydrogen atoms are slightly __ in charge.

polar covalent; negative; positive

_________ bonds form between water molecules.

Hydrogen

Each water molecule can form a maximum of ______ hydrogen bonds at a time.

two Signup and view all the answers

________ is the linking of like molecules. Think of this property as a 'water strider' walking on top of a pond due to _ tension created by hydrogen bonding between water molecules.

cohesion; surface Signup and view all the answers

__________________ is the clinging of one substance to another. Think of water adhering to another substance like the sides of a glass or a windshield.

adhesion Signup and view all the answers

______ is the movement of water molecules up a very thin tube called stomata and their evaporation from the stomates in plants. The water molecules cling to each other by and the walls of the xylem by _.

Transpiration; cohesion; adhesion Signup and view all the answers

Moderation of ___________ is possible because of water's high specific heat.

temperature Signup and view all the answers

Specific heat is the amount of heat required to ____ or lower the temperature of a substance _ degrees Celsius. Relative to most other materials, the temperature of water changes less when a given amount of heat is lost or __. The high specific heat of water makes the Earth's oceans relatively _ and able to support ____ quantities of life.

raise; one; gained; stable; large Signup and view all the answers

______________ of bodies of water by floating ice.

Insulation Signup and view all the answers

Water is less _______ as a solid than a liquid which is opposite of most other substances. Since ice is less _ it will float. This keeps large bodies of water from and moderates the .

dense; dense; freezing; temperature Signup and view all the answers

Water is an important _________________. (A substance something dissolves in).

solvent Signup and view all the answers

_____ substances are water-soluble. These include IONIC compounds, _ molecules like sugar and some proteins.

Hydrophilic; non-ionic polar Signup and view all the answers

___ substances like oils are nonpolar and will not _ in water.

Hydrophobic; dissolve Signup and view all the answers

The pH scale runs between ___ and and measures relative _ and __ of aqueous solutions.

0; 14; acidity; alkalinity Signup and view all the answers

Acids have an excess of ions and a pH below .

hydronium; 7 Signup and view all the answers

_ have an excess of ions and a pH above .

Bases; hydroxide; 7 Signup and view all the answers

Pure water is which means has a pH of .

neutral; 7 Signup and view all the answers

Buffers are substances that minimize changes in the _. They accept from solutions when they are in excess and donate _ when they are depleted.

pH; H+; H+ Signup and view all the answers

Carbonic acid (_____) is an important buffer in living systems. It moderates pH changes in _ plasma and the ____.

H2CO3; blood; ocean Signup and view all the answers

Study Notes

Structure and Properties of Water

Water consists of one oxygen atom and two hydrogen atoms.
The molecule is polar covalent, with a slightly negative charge on the oxygen and a slightly positive charge on the hydrogens.

Hydrogen Bonds

Hydrogen bonds form between water molecules.
Each water molecule can create a maximum of two hydrogen bonds.

Unique Properties of Water

Cohesion: The linking of like molecules allows phenomena such as surface tension, enabling insects like the water strider to walk on water.
Adhesion: The attraction of water molecules to different substances, illustrated by water’s ability to stick to glass or a windshield.
Transpiration: The process where water moves through plants, aided by cohesion among water molecules and adhesion to xylem walls.

Temperature Regulation

High specific heat of water enables moderation of temperature changes, which supports stable ecosystems.
Specific heat refers to the amount of heat necessary to change a substance's temperature by one degree Celsius; water's temperature fluctuates less than many other materials.

Ice Density and Insulation

Water is less dense as a solid (ice) than as a liquid, causing ice to float and providing insulation for aquatic environments, ensuring they do not freeze solid.

Solvent Properties

Water is a crucial solvent, dissolving various substances.
Hydrophilic substances, including ionic compounds and non-ionic polar molecules like sugar, easily dissolve in water.
Hydrophobic substances, such as oils, are nonpolar and do not dissolve in water.

pH Scale

Measures acidity or alkalinity within a range of 0 to 14.
Acids increase hydronium ions with a pH below 7.
Bases increase hydroxide ions with a pH above 7.
Pure water is neutral, having a pH of 7.

Buffer Systems

Buffers minimize pH changes by accepting excess H+ ions and donating H+ when depletions occur.
Carbonic acid (H2CO3) serves as a significant buffer in biological systems, regulating pH in blood and ocean water.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the unique properties of water through this engaging flashcard quiz. Each card helps reinforce key concepts surrounding water's molecular structure and its polar nature. Test your understanding and retention of water’s vital role in science.