Monday, January 13, 2020

High School Biology Lesson Plan – Properties of Water

Name:|Hailey Griffin| Lesson Plan Title:|Properties of Water| Grade Level: |10| Content Area:|Biology I| Sunshine State Standards or Common Core Standards:|Sunshine State Standards – SC. 912. L. 18. 12 – Discuss the special properties of water that contribute to Earth's suitability as an environment for life: cohesive behavior, ability to moderate temperature, expansion upon freezing, and versatility as a solvent. Behavior Objectives:|(Three parts: Condition, action, and measurement)Given a model of a water molecule, students will identify the oxygen and hydrogen atoms, the partial positive and negative areas of the molecule, and covalent bonds within the molecule. The learner will correctly identify the 4 main properties of water and give examples of each within 1 minute. Materials (including technology):|Students: Textbook, Pencil/Pen, PaperTeacher: Classroom board, markers, computer, Powerpoint presentation, Word processor, multiple copies of worksheets to pass out, Warm up :10 -15 Pennies, 10-15 Eye Droppers, Cups, Water Mini Labs: plastic petri dishes, paper clips, ethanol, water in eye droppers, glass slides, water, red food coloring, capillary tubes, straws, ice cubes, NaCl, salad oil in eye droppers, hot platesClosure: Koosh Ball| Hook/Anticipatory Set/Lead-In:Total Time: 15- 20 minutes|Prior to class, the instructor should gather the following supplies: Pennies, Eye droppers, Cups, Water.As students come into class, they should form groups of 3-4 people and pick up a one penny, one dropper, a small cup of water and return to their seats. They will also need a pencil/pen. Once every group has the proper materials, the instructor will hand out the accompanying worksheet (Appendix A). They should explain that each group is going to count how many drops of water will fit onto the top of a penny. The team with the most drops of water on their penny â€Å"wins†. As one student is dropping the water onto the penny, another should be count ing and recording the results.The other members of the group should be working on the worksheet, consulting their textbook for answers; this worksheet can be completed at home and is not to be turned in. | Procedures:Lecture: ~25 minutesWorksheet: Remaining class timeMini labs – Day 2, 45 minutes. |After the Penny Lab, the teacher should transition into a Powerpoint lecture on the properties of water (Powerpoint attached to lesson plan). The lecture should last for 25 minutes, enough time to get in the necessary information yet short enough to hold students’ attention.The following topics should be covered in the Powerpoint: the physical structure of a water molecule, states of matter, polarity, hydrophobic/hydrophilic substances, high heat capacity, cohesion/adhesion and surface tension, density and solubility. Once lecture is over, students will receive the Properties of Water worksheet (Appendix B) to work on during the rest of class and to complete as homework if n ot finished. This assignment will be due the following class period at the end of class and will be graded. The following class period, the teacher will set up the class into 6 â€Å"centers†.Each center is a mini lab and will focus on a certain property of water, the students should be able to use the knowledge they gained from the previous lesson to effectively answer questions about the properties of water. Each station will have a single worksheet (Appendix C) listing the procedure for the lab and 3-4 questions about the lab and property covered. Students must provide their own paper and copy down the questions and then respond; they can work together but must have their own answers. The work completed during lab time will be turned in a graded on the day of the test. minutes before class is over, the instructor should pass out a study guide and let students know that there will be a test the next class period, topics from both lecture and lab will be covered. | Guided an d Independent Practice: |On day 1, students will work together on the penny lab, and during lecture, students should be paying attention to the teacher. Finally, once the worksheet is handed out, students should be working independently. On day 2, students will be working in groups, rotating between centers; the teacher should be walking around class helping students when needed.On day 3 students will be working independently on the test. | Adaptations for ELL & ESE students|ELL students will have the opportunity to work with partners to receive peer support and help with complex concepts. Extra tutoring is available during lunch and afterschool. Vocabulary lists are available for pick up; students are encouraged to create flash cards to help them learn new vocabulary words. ELL students will also be given extended time to take tests. ESE students will be given extra time to complete assignments and complete tests.Complex directions will be clarified so the student is confident in w hat he/she is supposed to be doing. Students will be allowed to take short breaks during class and tests. | Closure Activity: |â€Å"Whip Around† Students quickly and verbally share one thing they learned in the class during the lesson. Students will pass around a koosh ball (or similar item) and whoever has the ball must give a short description of something they have learned. This could include topics from lecture, lab, or homework and could be an interesting fact, definition or short explanation of a concept.The teacher should be the first participant and will give an example of a good response, for example â€Å"Today I learned that solid water, or ice, forms a lattice structure which causes it to be less dense than liquid water, which makes it float. † This activity will end once everyone has shared their thoughts. If there is ample time and enough willing participants, this activity could also be used for students to gain extra credit points. Students who wanted to talk about additional concepts could earn up to 2 points extra credit towards their test.The previous day’s assignment should be collected. | Assessment/Evaluation:|On the start of the day 3, students will come into class and prepare for their exam. Once everyone is seated quietly the instructor should pass out the test in which students have approximately 40 minutes to complete (ESE and ELL students have more time). Once a student completes the test he/she should read quietly or work on other classwork. The lab assignment from day 2 should also be turned in for grading. | Appendix A Properties of Water: Penny LabTake a Guess: How many drops of water do you think will fit onto a penny? __________ Cohesion, adhesion, and surface tension are attractive forces between molecules and very important properties of water. Cohesion is the ability of water to â€Å"stick† to itself; it is a result of intramolecular forces (intra- inside, so this is adhesion within the molecul e). An example of cohesion is when you over fill a glass with water, the liquid rises above the rim of the glass but does not fall off the side; instead it bubbles up, which is also caused by surface tension.Surface tension is a special type of cohesion; it can be described as the â€Å"skin† on top of water, in the case of the overfilled glass, the surface tension caused the water to stick together and form the bubble over the rim, this property also allows some bugs to walk on water. Adhesion describes water sticking to other materials and is an intermolecular force (between neighboring molecules). Adhesion can be observed in the stem of a vascular plant; water molecules stick to the xylem tissue and â€Å"climb† up the plant. These properties occur because water is a polar molecule.A molecule of water is composed of 2 hydrogen atoms and 1 oxygen atom, because of the relationship shared between these atoms, one side become slightly more positive and the other slightl y more negative. These partial charges are symbolized by the Greek letter delta, or ?. The polarity of water molecules allows water to dissolve polar and charged substances, making water a good solvent. Molecules that are uncharged, such as fats and oils, usually do not dissolve in water and are called hydrophobic. Procedure: 1. Place a dry penny on a flat surface. 2.With the eye dropper, drip one drop of water onto the surface of the penny, one drop at a time. Have one student in your group keep track of the number of drops. 3. Observe the surface of the penny as the water builds up. 4. Once ANY amount of water has spilled over the edge of the penny record your final count of water drops. 5. Clean up your area and return materials to your teacher. Final Count: How many water droplets really fit onto the penny? ___________ Class Average ___________ Reflection: Explain your results in terms of cohesion and surface tension.What do you think would happen if we added soap, a hydrophobic substance, to the water before dropping it onto the penny? Explain your answer. Find a picture of a water molecule in your book, copy the drawing and label the following: oxygen molecule, hydrogen molecules, ? +, ? -, and draw the intramolecular bonds between the oxygen and hydrogen atoms. Appendix B Properties of Water 1. a. Draw the structure of water. Include the partial charges of each atom. b. Why is water considered to be a polar molecule? 2. a. What enables neighboring water molecules to hydrogen-bond to one another? b.How many hydrogen bonds can each water molecule form? 3. a. Explain the difference between adhesion and cohesion. Give an example of each. b. How do adhesion and cohesion explain capillary action? 4. What is surface tension? Give an example. 5. a. What is specific heat? b. Explain why water has such a high specific heat. c. Explain why it is cooler by the lake (or any body of water) in the summer and warmer by the lake in the winter. 6. a. Explain why ice is l ess dense as a solid than as a liquid. 7. a. Why is water called the universal solvent? What does polarity have to do with this? . How does water dissolve a substance like NaCl? Draw a picture illustrating this. 8. What do hydrophobic and hydrophilic mean? 9. List five special properties of water and give an example (other than ones from this worksheet) of each. Appendix C Center 1 – Can you float a paper clip? Procedure: Fill a plastic petri dish to overflowing with water. Without disturbing the surface of the water, start at the â€Å"lip† of the plastic bowl and slide the paper clip across onto the surface of the water. Observe the way the water â€Å"bends† under the paper clip. Record your observations.Repeat using ethanol in place of water. Questions: 1. What property (properties) of water is (are) demonstrated here? 2. How can the surface of water act this way? 3. Why did the paper clip not float on the ethanol? Center 2 – Can you overcome the attr action? Procedure: Using a dropper, place 2-3 drops of water on one glass slide. Lay the second glass slide over the first. Try to pull them apart. Record your observations. Repeat using dry slides. Questions: 1. What property (properties) of water is (are) at work here? 2. How are hydrogen bonds involved in this (these) property (properties)? . Explain why glass is described as hydrophilic. Center 3 – How does water move through plants? Procedure: Fill a capillary tube and then a straw with a red dye solution (red food coloring in water) and raise them to a vertical position. Record your observations. Questions: 1. What properties of water are at work here? How does water rise up the tube? 2. Why are these properties important to a plants survival? Center 4- Is a solid lighter than a liquid? Procedure: Put a cube of ice in a beaker labeled and filled with â€Å"alcohol† and another in a beaker labeled and filled with water.Observe where the ice cube is in relation to the surface of the solution. Quickly remove the ice cubes for the next group. Record your observations. Questions: 1. Why is the ice cube at the top or bottom of the alcohol? Water? 2. Why is frozen water less dense than liquid water? 3. Explain how this property of water is important to marine life. Center 5 – Like dissolves like Procedure: Place a spoonful of NaCl in a beaker of water and stir. Place 2 droppers full of salad oil in the beaker of water and stir. Record your observations. Questions: 1. Why does NaCl â€Å"dissolve† in the water? 2.Why is it essential for compounds like salt and glucose to be soluble in the water found in our body? 3. Does salad oil dissolve in water? Explain your answer. Center 6 – Does water boil sooner if salt is added? Procedure: Obtain 2 beakers, one labeled â€Å"deionized water† and the other â€Å"salt water†. Add 2 spoonfuls of salt to the beaker labeled â€Å"salt water† and stir to obtain a solutio n. Place each beaker, with a thermometer on it, on a hot plate and determine which beaker begins boiling first. Record your observations. Questions: 1. Does the addition of salt make the water boil faster or slower?Why? What does salt do to the boiling point of water? 2. Obtain an ice cube and add salt to it. What happened to the area of ice where the salt is applied? Why is salt applied to icy sidewalks or roads in the winter? What does salt do to the freezing point of water? Appendix D Properties of Water Test Name: ____________________ Period: ______ Properties of Water Test Review 1. Define the following vocabulary: Cohesion Adhesion Surface Tension Capillary action Hydrophobic Hydrophilic 2. How does water density change†¦. a. as the temperature of water increases ____________ b. s the salinity of water increases ____________ c. as the temperature of water decreases ____________ d. as the salinity of water decreases ____________ 3. What is a polar molecule? 4. What type of bonds exist between the atoms of a water molecule? 5. What type of bonds exist between the adjacent water molecules? 6. Why is water called the universal solvent? 8. What happens to the volume of water as it freezes? What happens to its density? True/False True False Water contracts (gets smaller) when it freezes. True False Water has a high surface tension. True False Condensation is water coming out of the air.True False It takes more energy to heat water at room temperature to 212o F than it does to change 212o F water to steam. Why is water called the universal solvent? What does polarity have to do with this? How many hydrogen bonds can each water molecule form? Differentiate between the intramolecular forces and the intermolecular forces at work inside and between water molecules. Please draw a water molecule. Label the following: oxygen molecule, hydrogen molecules, ? +, ? -, and draw the intramolecular bonds between the oxygen and hydrogen atoms.

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