Understanding Water's Unique Properties Supporting Life

MONDAY, OCTOBER 13TH, 2014 Bio.A.1.2.2: Describe the unique properties of water and how these properties Bio.A.1.2.2: Describe the unique properties of water and how these properties support life on Earth support life on Earth Objective: What makes water so important and unique? Objective: What makes water so important and unique? Warmup Warmup: : ***Brainstorm*** ***Brainstorm*** What properties do you remember about water? (ex. What properties do you remember about water? (ex. Freezing point, density, chemical formula, Freezing point, density, chemical formula, etc etc) ) Anything that you can remember .. Anything that you can remember ..

TUESDAY, OCTOBER 14TH, 2014 Bio.A.1.2.2: Describe the unique properties of water and how these properties Bio.A.1.2.2: Describe the unique properties of water and how these properties support life on Earth support life on Earth Objective: What makes water so important and unique? Objective: What makes water so important and unique? Warmup Warmup: : ***Brainstorm*** ***Brainstorm*** What properties do you remember about water? (ex. What properties do you remember about water? (ex. Freezing point, density, chemical formula, Freezing point, density, chemical formula, etc etc) ) Anything that you can remember .. Anything that you can remember ..

THE UNIQUENESS OF WATER HTTP://WWW.YOUTUBE.COM/WATCH?V=ASLUY2U1M-8

I. WHY IS WATER IMPORTANT TO ORGANISMS? 1. If you don t live in it, you carry it with you: water makes up 60 60- -95% 95% of most organisms. 2. It plays many roles in the body: Allows molecules & ions molecules & ions to move, collide and dissolve Decreases concentration in blood for easier movement/better pH levels movement/better pH levels Allows chemical reactions chemical reactions to occur Maintains a constant body temperature (homeostasis) body temperature (homeostasis) blood for easier

II. WHAT ABOUT WATERS STRUCTURE ALLOWS IT TO DO ALL THIS? 1. Water is polar (exhibits polarity) polar (exhibits polarity) Polar molecule Polar molecule molecule with an unequal distribution of charge; each molecule has a negative ( end. negative (- -) ) and positive (+) positive (+)

II. WHAT ABOUT WATERS STRUCTURE ALLOWS IT TO DO ALL THIS? 1. Water is polar (exhibits polarity) polar (exhibits polarity) Shape (^) of water indicates oxygen attracts more e hydrogen; oxygen acts ( hydrogen; oxygen acts (- -) and hydrogen acts (+) Water s overall charge = 10 p+ 10 e- zero Polar molecules are very attractive because (+) and (-) ends function like a magnet oxygen attracts more e- - than ) and hydrogen acts (+) than

II. WHAT ABOUT WATERS STRUCTURE ALLOWS IT TO DO ALL THIS? 1. Water is polar (exhibits polarity) polar (exhibits polarity) - - Because water is like a magnet: magnet: They (water molecules) attract: ions ions example: sodium (Na+) and chloride (Cl polar molecules polar molecules example: sugar (carbohydrate) water water Because water is like a sodium (Na+) and chloride (Cl- -) ) sugar (carbohydrate)

2. Water forms hydrogen bonds hydrogen bonds (bond between +/ polar molecule) polar molecule) Characteristics: Weak Weak bond formed/broken easily (bond between +/- - ends of a ends of a

CUT OUT WATER MOLECULES Part Part 1 1: : Draw a model of one water molecule. Draw a model of one water molecule. 1.) Show the number of protons, neutrons and 1.) Show the number of protons, neutrons and electrons in the shells of the atoms involved. electrons in the shells of the atoms involved. https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcS0Q74zeNtiPz1bw6b1SQDli9jjqHPvPajYnOPMgg0eVuIX3hqIxRUYTg

CUT OUT WATER MOLECULES Part 2: Part 2: Cut out a Cut out a model of one water molecule. model of one water molecule. 1.) Color the oxygen atoms of each water 1.) Color the oxygen atoms of each water molecule red. molecule red. 2.) Color hydrogen blue 2.) Color hydrogen blue 3 3.) Indicate the relative charge of each side of the .) Indicate the relative charge of each side of the water molecule by placing a plus or a minus on the water molecule by placing a plus or a minus on the correct sides. correct sides.

TUESDAY, OCTOBER 14TH, 2014 Bio.A.1.2.2: Describe the unique properties of water and how these properties Bio.A.1.2.2: Describe the unique properties of water and how these properties support life on Earth support life on Earth Objective: What makes water so important and unique? Objective: What makes water so important and unique? Warmup Warmup: What does it mean when we say that water is : What does it mean when we say that water is POLAR? POLAR? Draw a picture or explain it please. Draw a picture or explain it please.

PART 3: On your cut On your cut- -outs outs page: page: 1 1.) Color the oxygen atoms of each water molecule red .) Color the oxygen atoms of each water molecule red. . 2.) Color hydrogen atoms blue. 2.) Color hydrogen atoms blue. 3 3.) molecule by placing a plus or a minus on the correct sides molecule by placing a plus or a minus on the correct sides. . .) Indicate the relative charge of each side of the water Indicate the relative charge of each side of the water 4 4.) Cut out 5 molecules. .) Cut out 5 molecules. 5 5.) hydrogen bonds between each water molecule by drawing hydrogen bonds between each water molecule by drawing three black dots between them. three black dots between them. .) Arrange them to show Arrange them to show hydrogen bonds hydrogen bonds. Indicate the . Indicate the

II. WHAT ABOUT WATERS STRUCTURE ALLOWS IT TO DO ALL THIS? 2. Water forms hydrogen bonds hydrogen bonds (bond between +/ polar molecule) polar molecule) Characteristics: Weak Weak bond formed/broken easily Responsible for cohesion between like like molecules (example: H2O - H2O) Produces surface tension surface tension so insects, leaves can float on water Water molecules stick together to move against gravity (capillary action capillary action) (bond between +/- - ends of a ends of a cohesion intermolecular attraction

II. WHAT ABOUT WATERS STRUCTURE ALLOWS IT TO DO ALL THIS? 2. Water forms hydrogen bonds hydrogen bonds (bond between +/ polar molecule) polar molecule) Hold large molecules and H2O together. Adhesion intermolecular attraction of unlike Water forms droplets on leaves Water molecules stick together to move against gravity (capillary action capillary action) (bond between +/- - ends of a ends of a Adhesion the unlike molecules

II. WHAT ABOUT WATERS STRUCTURE ALLOWS IT TO DO ALL THIS? Like molecules Unlike molecules

MINILAB COHESION, ADHESION, SURFACE TENSION

III. WHAT OTHER PROPERTIES DOES WATER HAVE? 1. Has less density as a solid less density as a solid Water forms crystal-like bonds when it freezes, keeping the molecules at fixed distances from each other Low density Low density less tightly tightly packed Water expands when frozen and floats, allowing organisms Water expands when frozen and floats, allowing organisms to live underneath to live underneath

III. WHAT OTHER PROPERTIES DOES WATER HAVE? 2. Is a universal solvent universal solvent Dissolves many compounds such as carbohydrates and some proteins Allows chemical reactions to occur Allows chemical reactions to occur

III. WHAT OTHER PROPERTIES DOES WATER HAVE? 3. Has high heat of vaporization high heat of vaporization Amount of heat energy needed to change 1 g of 100 C boiling water to 100 C steam (you sweat and water evaporates off your skin to cool you) (you sweat and water evaporates off your skin to cool you)

III. WHAT OTHER PROPERTIES DOES WATER HAVE? 4. Has high specific heat high specific heat Amount of energy required to change 1 gram of water by 1 C (water resists change in temperature) (water resists change in temperature) Substances with H-bonds take longer to cool those w/o Allows organisms to maintain a stable internal environment Allows organisms to maintain a stable internal environment (homeostasis) (homeostasis) Allows water to resist temperature change Allows water to resist temperature change cool or heat heat than

MORE ABOUT SOLUTIONS: Water is known as the Universal Solvent: Solutions have 2 parts: Solute what is being dissolved Solvent what is doing the dissolving

NaCl Solution and dissolving

MORE ABOUT SOLUTIONS: pH Scale Measures the amount of hydrogen ions in a solution Low