Properties of Water and pH LESSON TWO Properties of Water and pH NEXT

Part 1: Properties of Water Review the following information about the properties of water to complete your flowchart. NOTE: Some of the slides will take you to internet resources filled with additional information Some of the slides may contain links to definitions NEXT

Molecular Structure & Polarity Water is a "polar" molecule, meaning that there is an uneven distribution of electrons resulting in a molecule with a both a positively and negatively charged region. Water has a partial negative charge near the oxygen atom due the unshared pairs of electrons, and partial positive charges near the hydrogen atoms. http://www.biology.arizona.edu/biochemistry/tutorials/chemistry/page3.html Covalent Bond NEXT **Click on “Covalent Bond” for the definition.

Definitions… Covalent Bond – when two atoms share one or more electrons In a water molecule, each hydrogen atom is covalently bonded to the oxygen via a shared pair of electrons. RETURN

Hydrogen Bonds Hydrogen Bond – the electrostatic attraction between the partial positive charge near the hydrogen atoms and the partial negative charge near the oxygen How one water molecule “sticks” to another http://www.biology.arizona.edu/biochemistry/tutorials/chemistry/page3.html NEXT

Click on “NEXT” when you are finished. Let’s review so far! Click on the bucket of water below to watch the short animation on water. Click on “NEXT” when you are finished. NEXT

Surface Tension & Capillary Action Click on the picture of the celery to the right to learn about surface tension, cohesion, adhesion, and capillary action! After visiting the website, click on the arrow to move on to the next slide. NEXT

Universal Solvent Water is called the "universal solvent" because it dissolves more substances than any other liquid. This means that wherever water goes, either through the ground or through our bodies, it takes along valuable chemicals, minerals, and nutrients. http://ga.water.usgs.gov/edu/waterproperties.html NEXT

Click on “NEXT” when you are all finished. Universal Solvent What is the difference between a solvent, solute, and a solution? Click on each word to find out! Click on “NEXT” when you are all finished. NEXT

SOLVENT Definition = A substance that dissolves a solute to create a solution. Identify the solvent below by clicking on the correct answer. Chocolate Milk Chocolate Milk

Remember to look closely at the definition! SORRY! Click here to try again! Remember to look closely at the definition! What would be doing the dissolving?

SOLUTE Definition = A substance that is dissolved in a solvent to create a solution. Identify the solute below by clicking on the correct answer. Chocolate Milk Chocolate Milk

Remember to look closely at the definition! SORRY! Click here to try again! Remember to look closely at the definition! What would be dissolved?

SOLUTION Definition = A mixture of two or more substances in which he molecules of the substances are evenly distributed Identify the solution below by clicking on the correct answer. Chocolate Milk Chocolate Milk

Remember to look closely at the definition! SORRY! Click here to try again! Remember to look closely at the definition! What would be the mixture?

CONGRATULATIONS! You were right! Click here to continue learning about solvents, solutes, and solutions!

Density Ice floats because hydrogen bonds hold water molecules further apart in a solid than in a liquid. Ice is less dense as a solid than a liquid. NEXT

Heat Capacity Water has a HIGH heat capacity (it takes a lot of energy to raise its temperature) WHY??? because the energy needs to first break the hydrogen bonds before it can raise the temperature of the water. NEXT

Part 2: Acids and Bases Read the following slides to review what pH is and to complete your pH scale… NEXT

What is pH? pH is a measure of how acidic/basic a solution is. The range goes from 0 - 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. NEXT

Click on “NEXT” when you are all finished. The pH Scale Label your pH scale to show the proper ranges of acids, bases, and neutral. Click on the clipboard to test the pH value of the substances listed on your worksheet. Record their value by placing the substance at their appropriate location on your pH scale. Click on “NEXT” when you are all finished. NEXT

Part 3: Review! Now it is time to review what you have learned in Lesson 2… Click on the dice below to play the vocabulary matching game. If you get stuck, review the list of vocabulary words and try again!