Pre­Unit Planning Planning Learning Experiences and Instruction

Teacher: Eva Santos_____________ Unit: Acids and Bases_____________

What teaching and learning experiences will equip students to demonstrate the targeted understandings?

Day 1: Students will learn about the properties of acids by answering a worksheet. Students will work in groups in the classroom. After each group has completed all the work, students will get back together as a class and come up with the properties of an acid. Students will learn about the properties of bases by answering a worksheet. Students will work in groups in the classroom. After each group has completed all the work, students will get back together as a class and come up with the properties of a base. Day 2: Students will examine the concepts of strength and concentration by testing several different substances using indicator paper. Students will then discuss as a class which of the substances are acidic and which of the substances are basic. Students will make a visual representation placing each of the substances in the appropriate space that accurately reflects its strength and concentration. Day 3: Students will perform an inquiry­based lab using titration techniques. Students will design a process that includes; identification of a problem, hypothesis, procedure, experimentation plan, conclusion, and any observations. Students will have a list of equipment that is available to them. Day 4: Students will have a post­lab discussion where the results of the lab are shared. Students will discuss their process and give supporting reasons for their conclusions. Students will identify strengths and weakness in experimentation as well as identify errors and ways that the experiment could be improved. Day 5: Students will be introduced to the topic of “Acid Rain.” Students will be asked to investigate using internet source and lab equipment the effects of acid rain in the environment and aquatic organism. Their assignment is to create a research paper explaining the results of their findings. Students will prepare for this presentation by researching articles and forming opinions on the topic.

Weekly Lesson Planning Unit: Acids and Bases Time Frame: 5days

Content Skills Assessment Activities

Monday

Acids and Bases Properties of acids Common acids Properties of bases Common bases Solutions of acids and bases

Make observations as students work together

Students will work together in a Peer­Tutoring style to answer the worksheet Collect activity sheets and homework

Have students present results to their peers

1.Peer tutoring 2.Worksheet

Tuesday

Measuring pH from acids and bases

Use of indicators to distinguish acids and bases

By adding drops of cabbage juice to a solution and watching the color change, students can determine if the pH of a solution is in an acidic range or a basic range.

Watching students perform the lab inquiry How they understand the relationship between the pH reading and indicators.

1.In class lab inquiry 2.Homework

Wednesday

Strength of Acids and Bases Strong and weak acids & bases pH of solutions

Compare strong acid with weak acids.

Describe how strong and weak acids differ in terms of concentrations of electrolytes

Students work homework problems on the board

1.Working problems from the homework on the board

Thursday

Acids, Bases, & Salts Neutralization Salts Titration

Apply the concept of titration by performing a lab Replicate how titration works after demonstration Perform calculations using Molarity

Lab Assessment: Students will be expected to turn in a lab report that accurately reflects their observations, outcomes, and conclusions according to a guided rubric

1.Inquiry Lab 2.Lab Report

Perform a titration lab

Friday

Acid Rain What is it? Formation of acid rain

Describe how acid rain affects other objects and the environment Infer how acid rain in the atmosphere affects other objects (i.e. statues, buildings, rocks or living organisms in the environment) Investigate how acid effects our environment

Students will do a web based research on acid rain location in the Bronx County and answer a lab questions. They will be assed in their presentation of data and the completion of their report according to a guided rubric.

1.Web research 2.Written report

Lesson Plan Unit Plan: Acids and Bases Topic: Naming and writing formulas for acids and bases Do Now: List at least three fruits that are acid Aim: How do we classify acids and bases?

Standards: New York City High School Science Standards S1a: Demonstrate an understanding of structure and properties of matter S4e: Demonstrate an understanding of the impact of science S5e: Identifies problems; proposes and implements solutions; and evaluates the accuracy, design, and outcomes of investigations S7d: Explains a scientific concept to other students Performance Objectives: Students Will Be ABLE TO (SWBAT):

1.Compare and contrast Arrhenius definition of both acids and bases 2.Compare and contrast between five different properties of acids and bases 3.Name strong acids and bases 4.Apply the definition of the Bronsted­Lowry definition to acids and bases 5.Compare Arrhenius theory to Bronsted­Lowry theory

Vocabulary: Arrhenius:

Base­ A substance that increases the concentration of hydroxide ions, OH­, in aqueous solution (hydroxide ions generators) Acid­ A chemical compound that increases the concentration of hydrogen ions, H+, in aqueous solution (hydronium ion generator)

Bronsted­ Lowry: Acid­ An ion or molecule that can donate a proton to another species Base­ Any atom, ion, or molecule that can accept a proton from another species.

Material Lists: Computer Internet Access Worksheet Safety and Disposal: N/A Anticipatory Opening: (3min) Acids and Bases Development of the lesson: (35min)

What the teacher does What the student does

1 Put up DO NOW, AIM, and HW; set up materials.

2 Go over Do Now

3 Show the video song 4 Develop concept of acids and bases, give definition 5 Ask a student to read the Aim

6 Mini lesson: Ask: where can we find acids and bases?

(Answer: Acids and bases can be found everywhere in the world around us).

Example of acids and bases: Lactic acid occurs in sour milk, citric acid in citric fruits, oxalic acid in rhubarb, malic acid in apples, and tartaric acid in wine. Baking soda, antacids, and lye all contain bases. Acids and bases are used widely used in in industry.

Students start Do Now. Students share their answers Students write concepts in their notebooks Student reads the Aim Students answer the questions

7 Characteristics of Acids and Bases: Soap and other bases have a bitter taste, feel slippery to the touch, and do not react when combined with most. Lemon juice and other acids usually have a sour test, sting when touched, and react strongly when combined with metals.

8 Ask: How acids and bases helped create the environment we live in now?

9 Break students into groups to complete the worksheet 10Answer Aim 11Have a student to read the homework from the board

Students will answer the questions in their worksheet Students write answer to aim in their notebooks. One student is chosen to write on the board

Differentiated instruction: Instruction is differentiated according to learner needs, to help all learners either meet the intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the specified indicator(s). SLD: Assign groups, assign specific tasks, provide activity sheet, assist certain groups with measuring and procedure

ELL: Assign groups (allow students to work/communicate with bilingual students), allow all students express data with drawings, highlight key words; give explanation in native language, if possible.

Summative Assessment Questions: (7min) What if we didn’t produce acids and bases? How would that affect us? Are acids and bases produced in other cultures? Are we the only ones dependent on them? How are different acids and bases used in other cultures? Homework: Brainstorm examples of an acid and two examples of a base that are present in your household. List the differences between an acid and a base. Notes for revision: N/A

Worksheet

1.Use this completion exercise to check your understanding of the concepts and terms that are introduced in this section. Each blank can be completed with a term, phrase, or number.

An acid is a compound that contains one or more_______ atoms and produces_____ when dissolved in water. There are rules for naming acids. For example, HBr is called_______ acid, whereas HNO3 is called______ acid. A base is a (n)________ compound that produces________ when dissolved in water. Ionic compounds that are bases are named in the same way as other______ compounds, that is, the same of the_____ is followed by the name of the_________.

2.Write the formula for each acid or base

a Magnesium Hydroxide b Hydrofluoric acid c Phosphoric acid d Lithium hydroxide

3.Short Answer Answer the following questions according to the Brønsted­Lowry definitions of acids and bases:

a. What is the conjugate base of H2SO3? b. What is the conjugate base of NH4? c. What is the conjugate base of H2O? d. What is the conjugate acid of H2O? e. What is the conjugate acid of HASO4?

Using the Arrhenius definition of a base, explain how LiOH qualifies as a base. Using the Brønsted­Lowry definition of a base, explain how LiOH qualifies as a base. Using the Lewis definition of a base, explain how LiOH qualifies as a base. Determine the Brønsted­Lowry conjugate acid­base pairs in each of the following equations:

2 HNO3 + NH3 NO3­ + NH4

+ 3 Br­ + H3O+ HBr + H2O 4 C2H3O2H + LiOH LiC2H3O2 + H2O 5 H3PO4 + H2O H2PO4

­ + H3O+ 4.Name the following acids and bases:

1) NaOH _______________________________________ 2) H2SO3 _______________________________________ 3) H2S _______________________________________

4) H3PO4 _______________________________________ 5) NH3 _______________________________________ 6) HCN _______________________________________ 7) Ca(OH)2 _______________________________________ 8) Fe(OH)3 _______________________________________ 9) H3P_______________________________________

5.Write the formulas of the following acids and bases: 10) hydrofluoric acid _______________________________________ 11) hydroselenic acid _______________________________________ 12) carbonic acid _______________________________________ 13) lithium hydroxide _______________________________________ 14) nitrous acid _______________________________________ 15) cobalt (II) hydroxide _______________________________________ 16) sulfuric acid _______________________________________ 17) beryllium hydroxide _______________________________________ 18) hydrobromic acid _______________________________________

6.Listed below are some of the properties of acids and bases. Fill in the blanks with the appropriate word, acids or bases:

a) _______ produce hydrogen ions (H+) in solution e) _______ have a sour taste b) _______ has a bitter taste f) _______ have a slippery, soapy feel c) _______ produce hydroxide ions (OH­) ions g) _______ react with acids to form salts d) _______ react with bases to form salts h) _______ react with many metals

7.Match these substances with their chemical formulas:

___1. table salt ___2. milk of magnesia ___3. water ___4. stomach acid ___5. sugar ___6. limewater ___7. household ammonia ___8. hydrogen peroxide ___9. chalk ___10. drain cleaner (lye) ___11. vinegar ___12. battery acid

a) HCl b) CaCO3 c) Mg(OH)2 d) H2O2 e) HC2H3O2 f) H2O g) NH4OH h) C12H22O11 i) Ca(OH)2 j) H2SO4 k) NaOH l) NaCl

Lesson Plan

Unit Plan: Acids and Bases Topic: Measuring pH of common acids Do Now: Have you ever experienced pain when foods such as lemon or ketchup came in contact with a sore spot in your mouth? What did it feel like? Why? Aim: What methods can be used to determine whether a solution is acidic or basic? Standards: New York City High School Science Standards S1c: Demonstrate an understanding of chemical reactions S4e: Demonstrate an understanding of the impact of science S5f: Woks individually and in teams to collect and share information and ideas. S6b: Records and stores data using a variety of formats S8a: Demonstrate scientific competence by completing a controlled experiments Performance Objectives: Students will be able to (SWBAT):

1 Identify a solution as acidic or basic using an indicator. 2 Predict if common household substances are acids or bases. 3 To apply the concept of pH by using litmus paper 4 Describe the results of the investigation and characteristics of each substance.

Vocabulary: Indicator: A material that has the property of changing color in the presence of an acid or a base. pH: A scale that measures the concentration of hydrogen ions in a solution, pH= ­log[H3O+] Review of previous vocabulary Base: A substance that can accept hydrogen ions Acid: A substance that can donate hydrogen ions Material Lists:

Computer

Internet Connection Various Solutions containing: Baking Soda Solution, Ammonia, Windex, Lemon Juice, Vinegar, Coffee, Table Salt Solution, Water, Red

Cabbage Juice, ammonia, milk, and tums antacid Paper Towels Litmus Paper Tweezers Small clear cups

∙ Safety and Disposal:

Ammonia is a weakly basic solution and will irritate the eyes. Vinegar is a weakly acidic solution and will irritate the eyes. Dispose all materials through the drain with lots of running water

Anticipatory Opening: (4min) Use computer with Internet access to show the following video: Acids and Bases| Call Me Maybe. Development of the lesson: (35 mins)

What the teacher does What the student does

1 Put up DO NOW, AIM, and HW; set up materials. 2 Go over Do Now; ask students to share their answers 3 Show the video song 4 Ask a student to read the Aim 5 Ask: how can we determine the pH of solution? (Answer: using

a pH meter or litmus paper, and indicators) 6 What household products are basic or acidic? (Answer: basic,

ammonia, baking soda, Windex. Acid, lemon juice, bleach, vinegar.)

7 Show students how to measure the pH adding two drops of the indicator, and by using the litmus paper

8 Students are broken up into groups. One student from each group come up to a central area to collect the materials: labeled cups or jars with six solutions (2 acidic, 2 basic, 2 neutral) grouped so no one person will test two neutral solutions.

Students start Do Now. Students pay attention to the video Students answer questions Getter pick up materials

9 The stations also have tweezers for each student, paper towels for spills, and small torn pieces of litmus paper.

10Students make the following chart on the board

Material

pH litmus paper

indicator Observations

Ammonia

Windex

Lemon Juice

Vinegar

Coffee

Table Salt Solution

water

milk

Solution: one can determine if the solution is acidic, neutral or basic. With litmus paper it is easy to remember Acid turns Red and Bases are Blue (alliteration).

11A chart is given and the color is matched with the colors on the chart and the pH is estimated by the corresponding number (0­6 acidic, 7 neutral, 8­14 basic).

12Have students discard the waste and clean up. 13Develop the concept of pH and indicator; give definition 14Answer the Aim. 15Ask: Vinegar is a solution of acetic acid in water. A solution of

ammonia in water can neutralize the acidity of vinegar. What can be concluded about ammonia? (Solution: From this can be concluded that ammonia is….. a basic solution.)

Students record observations in their notebooks Students analyze data Students write definitions and answer to the aim in their notebooks Students write answer to aim in their notebooks. One student is chosen to write on the board

16Have a student to read the homework from the board.

Differentiated instruction: Instruction is differentiated according to learner needs, to help all learners either meet the intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the specified indicator(s). Resource Student: Students will be paired with other students in the class for the group and lab activities. Students will have several ways in which they can complete their experiment. Non­Native English Speaker: Students may use the Internet to access information in native language, they may use visual representations or they may use their peers. If there is a person experienced in that language ask them to assist in this students learning. Gifted Student: These students will be asked to be group leaders during labs and activity based learning. Summative Assessment Questions: (6min)

1 What is meant by "neutral"? What does pH measure? 2 From the experiment, what materials are acids, bases or neutral? 3 Explain the difference between a strong acid and a weak acid 4 How you will define an acid? 5 Do you know the pH value of any substance? Which one and what is its pH? 6 Describe the pH scale

Homework: Brainstorm household products you can use to perform a similar experiment. Use at least two but no more than 4 products from your refrigerator Complete the homework problems handout for next class. Notes for revision: N/A

Homework

1. Fill in the missing information:

[H+] pH pOH

1 x 10­5

3

2

2.5 x 10­3

6

1

[H+] [OH]

1 x 10­4

1 x 10­8

1 x 10­10

1 x 10­2

2 x 10­6

3.3 x 10­7

4.8 x 10­3

2. State whether each chemical is an acid, a base, or a salt. If it is an acid or a base, state whether it is strong or weak:

1. H2SO4 ________________ _________________

2. Mg(OH)2 ________________ _________________

3. KBr ________________ _________________

4. HI ________________ _________________

5. HC2H3O2 ________________ _________________

6. NH4OH ________________ _________________

7. HNO3 ________________ _________________

8. Li2CO3 ________________ _________________

9. NaOH ________________ _________________

10. HF ________________ _________________

3. Use the following key:

a) Acid b) Base c) Both Acid and Base

___1. tastes bitter

___2. electrolyte

___3. increases [OH]

___4. turns cabbage pink

___5. neutralizes NaOH

___6. increases [H+]

___7. tastes sour

___8. neutralizes HCl

___9. feels slippery

___10. decreases [OH]

___11. turns cabbage blue/green

___12. proton donor

___13. decreases [H+]

___14. corrosive

___15. proton acceptor

4. From the information given, determine whether the following solutions would most likely be acidic, basic, or neutral:

a) The solution has a salty flavor: ____________________________ b) The solution makes your hands feel slippery: _________________

c) The solution smells like broccoli: ___________________________ d) The solution conducts electricity: ___________________________ e) The solution can clean the tops of stoves: ___________________ Write an equation for the dissociation (ionization) of the following acids in water: (follow example:) a) HClO4 ­­­> H+ + ClO4­ d) H2S b) H2SO4 e) HCl c) HC2H3O2 f) HNO3

5 Match the column of the right with the left Acid 2. Base 3. Neutral 4. Neutralize 5. Acid Rain

A. To mix acids and bases to cancel each other out and make salt water. B. A compound that adds H+ ions to water. C. Equal number of H+ and OH– ions; water is an example. D. A compound that adds OH– ions to water. E. When pollution causes rain to be acidic (pH of less than 5.6).

1. pH 2. Salt Water 3. Strong Acid 4. Weak Base 5. Weak Acid

A. The measure of acids and bases. B. A compound that adds a few OH– ions to water. C. The product of a neutralization reaction between an acid and a base. D. A compound that adds a few H+ ions to water. E. A compound that adds a lot of H+ ionsto water.

6. Circle the acids and underline the bases 7. Solution A (pH 4); Solution B (pH 2) Which one has more H+ ions?

HCl H2(SO4) Mg(OH)2 H2(CO3) NaOH Ca(OH)2 H3PO4 LiOH HNO3

Which one has less OH– ions?

Solution A (pH 11); Solution B (pH 13) Which one has more OH­ ions? Which one has less H+ ions?

8.Acids or Bases? (below)

Has fewer OH– ions: Has more H+ ions: Has fewer H+ ions: Tastes sour:

Has more OH­ ions: pH of 1 to 7: pH of 7 to 14:

Feels slippery:

Lesson Plan Unit Plan: Acids and Bases Topic: Strength of Acids and Bases Do Now: Why sulfuric acid and not acetic acid was used as a crime method in the past? How can we tell if an acid is strong or weak? Aim: How do we measure the strength of an acid or a base? Standards: New York City High School Science Standards S1c: Demonstrate an understanding of chemical reactions S4e: Demonstrate an understanding of the impact of science S5e: Identifies problems; proposes and implements solutions; and evaluates the accuracy, design, and outcomes of investigations S7d: Explains a scientific concept to other students Performance Objectives: Student Will Be Able To (SWBAT):

1.Compare strong acid with weak acids. 2.Describe how strong and weak acids differ in terms of concentrations of electrolytes

Vocabulary: Strong Acid: an acid that ionizes completely in aqueous solution to form ions, one of which is the hydronium ion Weak Acid: an acid that is a weak electrolyte (does not ionize completely­does not proceed to complete reaction). Strong Base: an ionic compound that is very soluble in water. It fully dissociates in solution Weak Base: a base that is a weak electrolyte (does not fully dissociate) Material Lists: Homework sheet from previous day Safety and Disposal: N/A

Anticipatory Opening: (3min) Give students a riddle (written on the board): Johnny drank some liquid Now he drinks no more What he thought was H2O Was H2SO4 Ask students what this could mean of an acid or base How does this play into safety in the science lab? (Don’t drink anything; make sure everything is labeled correctly, etc.) Why would H2SO4 be so corrosive that Johnny couldn’t drink anymore? What is the proof? Development of the lesson: (35mins)

What the teacher does What the student does

1.Put up DO NOW, AIM, and HW; set up materials. 2.Go over Do Now; 3.Go over the riddle; ask: Ask students what this could

mean of an acid or base? How does this play into safety in the science lab? (Don’t drink anything; make sure everything is labeled correctly, etc.)Why would H2SO4 be so corrosive that Johnny couldn’t drink anymore? What is the proof?

4.Ionization was defined as certain covalently bonded molecules reacting with water and producing ions in solution. Ionization reactions involve chemical changes. It is the amount of ionization that is essential in determining if an acid is strong or weak. Strong acids are defined are ones that completely ionize or

undergo ionization (See Equation 1).

Students start Do Now. Students answer the questions orally Students copy notes on their notebook

5.Unlike their strong acid counterparts, weak acids do not ionize . The less ionization that takes place, the weaker the acid since there will be fewer ions in solution.

6.There are only six common strong acids. These acids are hydrochloric acid, perchloric acid, nitric acid, hydrobromic acid, sulfuric acid, and hydroiodic acid. Each of the acids, like , completely ionize in water.

7.Students work the homework problems from previous day on the board

8.Answer Aim 9.Have a student to read the homework from the board

Students go to the board Students write answer to aim in their notebooks. One student is chosen to write on the board

Differentiated instruction: Instruction is differentiated according to learner needs, to help all learners either meet the intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the specified indicator(s). SLD: Assign groups, assign specific tasks, provide activity sheet, assist certain groups with measuring and procedure

ELL: Assign groups (allow students to work/communicate with bilingual students), allow all students express data with drawings, highlight key words; give explanation in native language, if possible.

Summative Assessment Questions: (6min) 1. What is the difference between a strong and weak acid? Show an example of each.

2. In terms of electrolyte solutions, how would you distinguish between a strong acid and a weak acid?

3. All of the following are weak acids except?

a.

b.

c.

d.

4. Which compound is a strong acid?

a.

b.

c. formic acid

d. perchloric acid

5. Which one of the following compounds is not a strong electrolyte?

a.

b.

c.

d.

6. Which of the following is usually referred to as strong acid in water solution? Write the ionization reactions.

a. d.

b. e.

c. f.

Homework: TITRATION OF AN ACID WITH A BASE PRE­LAB *Show all of your work for full credit 1. How will you know when your titration is finished? ______________________________________________________________________________ ______________________________________________________________________________

2. Label the pH scale below with acid, base and neutral, indicating numbers for each. 3. On the scale above, use an arrow to show where your equivalence point is located. 4. Show the neutralization reaction that occurs between hydrobromic acid (HBr) and lithium hydroxide (LiOH). 5. What is the concentration of 10.00 mL of HBr if it takes 5 mL of a 0.253 M LiOH solution to neutralize it? Notes for revision: N/A

Lesson Plan Unit Plan: Acids and Bases Topic: Acids, Bases & Salts Titrations DO Now: What do you already know about pH? List three facts about pH Aim: What do you think is the purpose of this lab? Standards: New York City High School Science Standards S5b: Uses concepts from Science Standards 1 to 4 to explain a variety of observations and phenomena S6a: Uses technology and tools to observe and measure objects, organisms, and phenomena, directly, indirectly, and remotely, with appropriate consideration of accuracy and precision S7a: Represents data and results in multiple ways S8a: Demonstrate scientific competence by completing a controlled experiment Performance Objectives: Students Will Be Able To (SWBAT):

1.Apply the concept of titration by performing a lab 2.Replicate how titration works after demonstration 3.Perform calculations using Molarity

4.Perform a titration lab

Vocabulary: Neutralization: a mix of strong acid/strong base to get a neutral solution. Titration­the operation of gradually adding one solution to another to reach an equivalence point Equivalence point: the point in titration when the amount of added base or acid exactly equals the amount of acid or base originally in solution Material Lists: Sodium hydroxide solution [NaOH], 0.1M beakers, 250 mL Erlenmeyer flask, 250 mL Hydrochloric acid [HCl], unknown, buret, 25 or 50 mL ring stand Phenolphthalein indicator, buret, clamp Safety and Disposal: • Hydrochloric acid and sodium hydroxide are caustic! Avoid contact with the skin and eyes. • Safety goggles must be worn at all times; gloves are optional but highly recommended. • Sometimes chemicals from previous labs still remain in glassware and on other lab equipment; wash all lab equipment before and after performing this lab. • Wash your hands thoroughly after completing this lab.

Anticipatory Opening: (3min) The Bromthymol Blues Development of the lesson: (2class periods­37min)

What the teacher does What the student does

1.Put up DO NOW, AIM, and HW; set up materials. 2.Go over Do Now; have students answer on the board 3.Show the video song 4.Give introduction to the lab: One common task that chemists

must perform is to determine the concentration of a chemical using titration. There are a variety of reasons that this may be necessary, ranging from finding an unlabeled container in the

Students start Do Now. Students write information on their notebooks

stock room to applying forensic techniques in order to identify a sample at a crime scene. In this experiment you will titrate a measured volume of HCl with a solution of NaOH of known concentration. The acid and the base react with one another according to the equation: HCl (aq) + NaOH (aq) → NaCl (aq) + H2O (l) During the first stages of the titration, the NaOH will be completely neutralized, and an excess of acid will remain. However, at the theoretical endpoint, the acid and the base will have neutralized one another exactly, and the phenolphthalein indicator will turn pink when the acid is completely neutralized and a slight excess of base is present. In this titration, a successful endpoint is achieved if one drop of base turns the solution in the flask from colorless to a very faint pink, and at this point, the number of moles of NaOH used will be equal to the number of moles of HCl in the unknown solution. 5. Explain the procedure for titration 1. Obtain approximately 120 mL of NaOH in a 250 mL beaker. 2. Rinse the buret with approximately 10 mL of the NaOH solution, and let the liquid drain through the buret tip into an empty 250 mL "waste" beaker. Repeat this procedure twice more, using new 10 mL sample of NaOH solution each time. 3. Refill the buret so that the meniscus of the solution is above the 0 mL mark. Position the buret in a double buret clamp on a ring stand. Let some of the solution run rapidly from the buret to expel all air bubbles from the tip and to bring the level of the solution down to the calibrated region of the buret. If there is a drop of solution hanging on the tip of the buret, remove it by touching the drop to the inside wall of the 250 mL beaker. 4. Read the initial volume of the NaOH solution at the bottom of the meniscus. Your eye must be at the same level as the meniscus. 5. Pour 20.0 mL of HCl into a clean 250 mL Erlenmeyer flask. Add two drops of phenolphthalein indicator. Place the Erlenmeyer flask under the tip of the base buret; a piece of white paper placed under the flask will make it easier to see the color changes. While continuously swirling the flask to ensure

thorough mixing, run in the NaOH solution from the buret. Initially, a pink color will appear at the point where the NaOH comes in contact with the solution in the flask, but this color disappears quickly. As the endpoint nears, the color will disappear more slowly. Eventually, the NaOH should be added drop by drop until one drop turns the entire solution in the flask pink. This pink color should remain for at least 15 seconds while the solution is being swirled. 7. If you overshoot the endpoint, you will have to discard the solution and begin again. When you have reached a satisfactory endpoint, read the final volume of the buret and record the volume of NaOH used in your data table. 8. Refill the buret and repeat steps #3­7 twice more, using a clean Erlenmeyer flask. Additional Clean­up and Disposal 1. Drain your buret into the waste beaker and rinse it with tap water. 2. Wash any remaining solutions and materials down the sink. 6. Data Students should create a data table in the lab write­up that looks something like this: Trial 1 Trial 2 Trial 3

Initial Buret Volume

Final Buret Volume

Volume of base (mL)

Volume of base (L)

Moles of base Moles of Acid Volume of acid

(L) 0.020 0.020 0.020

Acid

Students write down their observations and data in their notebooks

concentration Average

concentration

7. Calculations (students include these answers in their Conclusion!) 1. For each trial, calculate the number of moles of NaOH used. 2. The number of moles of NaOH used is equal to the number of moles of HCl reacted. Based on the results in the previous calculation, determine the concentration of HCl for each trial. 3. Students obtain the accepted concentration of HCl from the teacher. Using the average experimental concentration of HCl, determine the percent error for this lab.

8. One student repeats the procedure 9. Answer Aim 10. Have a student to read the homework from the board

Student repeat the procedure Students do all calculations in their notebooks Students write answer to aim in their notebooks. One student is chosen to write on the board

Differentiated instruction: Instruction is differentiated according to learner needs, to help all learners either meet the intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the specified indicator(s). Resource Student: Students will be paired with other students in the class for the group and lab activities. Students will have several ways in which they can complete their experiment. Non­Native English Speaker: Students may use the Internet to access information in native language, they may use visual representations or they may use their peers. If there is a person experienced in that language ask them to assist in this students learning. Gifted Student: These students will be asked to be group leaders during labs and activity based learning. Summative Assessment Questions: (5min)

1 What is the main purpose of a titration?

2 Circle the correct answer: The indicator, phenolphthalein, turns pink when a solution is acidic or basic?

3 (A) Why is it important for a chemist to stop a titration when the solution is only beginning to change color?

(B) What is one way a chemist could get a solution to return to its colorless state?

4 In groups of 4 (2 groups together), come to the front table and observe Mr. Mitchell demonstrate the use of a titration apparatus.

A What did you notice about the indicator as sodium hydroxide was initially added to the flask?

B Why it is important to swirl the solution as the NaOH is added?

C When reading a buret, there are 2 important procedures that must be followed. What are these 2 procedures?

Homework:

1.Why does the pink color, which forms at the point where the NaOH comes into contact with the solution in the flask, disappear more slowly near the endpoint?

2.Why is it a good idea to carry out titrations in triplicate? 3.Would the addition of several milliliters of distilled water to the Erlenmeyer flask during the titration affect the results of the titration?

Explain your answer. 4.Errors

a. Describe two possible errors you may have committed in this lab that may have somehow affected your results. b. Explain the specific steps you will take to avoid each of these errors in the future.

5.Conclusion Write two or more paragraphs summarizing your results, examining the validity of your prediction, and explaining your calculations.

Notes for revision: N/A

Scoring Rubric for Lab Report Lab Partners _________________________________________ Score: ____ CRITERIA RATING SCORE EXEMPLARY

10 COMPETENT

:9 MINOR FLAWS

8 NEARLY

SATISFACTORY:7

FAILS TO

COMPLETE: 5

UNABLE TO BEGIN

EFFECTIVELY: 3

MADE 0 OR NO

ATTEMPT

Structure Responses are concise, clear, and complete

in describing the

Responses are FAIRLY

concise, clear and complete in describing

Completes the experiment

satisfactorily but the

explanation(s)

Begins the experiment

satisfactorily but omits significant parts or fails to

Experiment and its explanation of the structure and properties of matter are

Explanation is omitted

Does not begin

experiment Does not submit lab

structures and properties of matter.

the structures and properties of matter.

of the structures and properties of matter may

be slightly

ambiguous or unclear.

complete. May misuse

scientific terms

not clear, concise, or accurate

Incorrect use of scientific terms.

Major flaws in concept mastery.

report

Data Includes some graphic

representation of data or results.

MAY include some graphic representation of data or results.

Graphic representations

may be incomplete, inappropriate or unclear

Graphic representation of data may be incorrect or omitted.

Graphic representation of data does not reflect

the experiment or is omitted.

Graphic representation is omitted.

Graphic representation is omitted.

Procedure Shows

understanding of ALL

processes, procedures, and apparatus involved.

Shows understanding of MAJOR processes, procedures, and apparatus

used.

Shows incomplete

understanding of processes, procedures, and apparatus

used.

. Shows incomplete understanding of processes, procedures, and apparatus

used.

Shows incomplete

understanding of processes, procedures, And apparatus

used.

Does not distinguish what

information is needed for successful completion.

Does not distinguish what

information is needed for successful completion.

Hypothesis

Proposes a hypothesis.

Proposes a hypothesis.

Hypothesis may be incomplete, inappropriate or

unclear.

Incorrect or incomplete hypothesis.

Hypothesis does not reflect the experiment or is omitted.

Hypothesis is omitted.

Hypothesis is omitted.

Results Analyzes results IN

TERMS OF THE HYPOTHESIS.

Analyzes results

Analysis may be incomplete, inappropriate, or unclear.

Incorrect or incomplete analysis.

Analysis does not reflect the experiment or is omitted

Analysis is omitted

Analysis is omitted

Conclusion

Draws correct inferences and conclusions from results.

Draws ACCEPTABLE inferences and conclusions

from results.

Inferences and conclusions may be incomplete, inappropriate, or unclear

Incorrect or incomplete

inferences and conclusions.

Inferences and conclusions

does not reflect the experiment or is omitted.

Does not make an attempt at solution.

Does not make an attempt at solution.

Lesson Plan Unit Plan: Acids and Bases Topic: Acid Rain DO Now: Discuss with a partner what would happen to living organisms in streams that contain a significant increase in concentration of acid in the water. Record your inferences in your science notebook. Aim: What is acid rain and how does it affect living organisms and humans? Standards: New York City High School Science Standards S4c: Demonstrate an understanding of health S4d: Demonstrate an understanding of the impact of technology S5c: Use evidence from reliable sources to develop descriptions, explanations, and models; make appropriate adjustments and improvements S6a: Uses technology and tools to observe and measure objects, organisms, and phenomena, directly, indirectly, and remotely, with appropriate consideration of accuracy and precision S8d: Demonstrate scientific competence by completing secondary research Performance Objectives: Students Will Be Able To (SWBAT):

1.Describe how acid rain affects other objects and the environment 2.Infer how acid rain in the atmosphere affects other objects (i.e. statues, buildings, rocks or living organisms in the environment) 3.Investigate how acid effects our environment

Vocabulary:

Acid rain ­ precipitation, as rain, snow or sleet, containing relatively high concentrations of acid­forming chemicals: formed from coal smoke,

chemical manufacturing and smelting, that have been released into the atmosphere and combined with water vapor; harmful to the environment

Atmosphere ­ the gaseous envelope surrounding the earth; the air Acid deposition ­acidic material that falls from the atmosphere to the earth in either wet (rain, sleet, snow, or fog) or dry (gases and particles)

forms. Review from previous vocabulary: pH scale ­ used to express the acidity or alkalinity of a solution on a scale of 0 to 14, where less than 7 represents acidity, 7 neutrality, and more

than 7, alkalinity; each unit change on the pH scale represents a 10­fold change in acidity

Material Lists: Computer Internet Access to EPA Acid Rain Student Site Safety and Disposal: N/A Anticipatory Opening: (3min) Acid Rain Development of the lesson: (40 min)

What the teacher does What the student does

1. Put up DO NOW, AIM, and HW; set up materials. 2. Go over Do Now; 3. Show the video 4.Ask: What pH is needed for living organisms to be able to

survive? (Answer: pH7). How pollution does affect rain? (Answer: it makes acidic less than pH 5.6)

5.Introduce concepts of acid rain, atmosphere, and acid deposition; give definition.

6.Effects of Acid rain: it can kills plants, cause asthma and other physical problems. Acid rain also eats away statues and historical landmarks. The Roman ruins, the pyramids of Egypt, and other treasures of the world are being slowly dissolved away by acid rain. More damage has been done in the last century than in the last 2,000 years. Without stopping pollution (and acid rain) these treasures may be lost forever

7.Show students the EPA students website: EPA Acid Rain Student Site

8.Students explore the causes and effect of Acid Rain 9.Students discover what is being done and how they can get

Students start Do Now. Students answer the questions Students copy definition in the notebook Student take notes in the notebook

involve 10.Answer Aim 11.Have a student to read the homework from the board

Students write answer to aim in their notebooks. One student is chosen to write on the board

Differentiated instruction: Instruction is differentiated according to learner needs, to help all learners either meet the intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the specified indicator(s). Resource Student: Students will be paired with other students in the class for the group and lab activities. Students will have several ways in which they can complete their experiment. Non­Native English Speaker: Students may use the Internet to access information in native language, they may use visual representations or they may use their peers. If there is a person experienced in that language ask them to assist in this students learning. Gifted Student: These students will be asked to be group leaders during labs and activity based learning. Summative Assessment Questions: (2min) What do you think causes acid rain? How acid rain affects the environment? Homework: Explore the effect of acid on the environment through researching acid rain using the website link: NTN sites. Work in pairs and look at the acid rain trends of The Bronx. Also look at the trends of other locations and use this data to infer the cause of acid rain. Each pair of students will explain their finding to the class (25 minutes) you will tell the cities you researched, the trends observed, and what this could mean about the sources of acid rain. (15 minutes) Notes for revision: N/A

Scoring Rubric Performance Criteria Evidence Points or Rating Students should determine the cause of acid rain

Completion “Acid Rain” portion of the activity sheet

Students should be able to explain inferences made from data

Explaining trends of locations to class and inferences made.

Students should explain the effect of acid on wildlife.

Completion “Acid Rain” portion of the activity sheet

2 – Completes activity and classification/explanation 1 – Completes activity but has incomplete classification/explanation 0 – does not complete activity or explanation

Name_______________________ Class___ Date________________________

Acids and the Environment Acid Rain— What do you think causes acid rain? How could you test your hypothesis? 1. Open the Internet Brower and go to http://nadp.sws.uiuc.edu/sites/ntnmap.asp? 2. Click on the Bronx on the map. 3. Find and click on NY06 – Bronx. This collection station is in Bronx County. 4. Find and click on “Trend Plots” 5. Fill in the “Lab pH” bubble and then “Create Plot” What is this most current pH reading of the rain in Giles County? ______

6.Consider your hypothesis above. Think about what areas of the country you can look at data from to test your hypothesis. Record your data below.

City pH

7.What trend did you observe between your cities? 8.What does this say about what the source of acid rain could be? 9.Does this align with your hypothesis? Why or why not?

Name_____________________ Class___ Date______________________

Acids and the Environment Acid and Wildlife— 1. Put on your safety goggles. 2. Prepare and label the following jars: Control Jar a – 30mL of lake water Jar #1a – 2mL of acid solution and enough lake water to make 30mL Jar #2a – 4mL of acid solution and enough lake water to make 30mL Jar #3a – 8mL of acid solution and enough lake water to make 30mL Jar #4a – 16mL of acid solution and enough lake water to make 30mL Jar #5a – 30mL of acid solution 3. Use pH paper to determine the pH of each solution. Record in the data chart on the back. 4. Add five Daphina to each jar. Make sure you do this how I demonstrated. If you have a question, ask FIRST! 5. Record the time you put the Daphina in. Time:_______ 6. Prepare and label the following jars: Control Jar b – 30mL of lake water Jar #1b – 2mL of acid solution and enough lake water to make 30mL Jar #2b – 4mL of acid solution and enough lake water to make 30mL Jar #3b – 8mL of acid solution and enough lake water to make 30mL Jar #4b – 16mL of acid solution and enough lake water to make 30mL Jar #5b – 30mL of acid solution 7. Use pH paper to determine the pH of each solution. Record in the data chart below. 8. Add five brine shrimp to each jar. Make sure you do this how I demonstrated. If you have a question, ask FIRST! 9. Record the time you put the brine shrimp in. Time:_______ 10. Record observations for all of the jars in your science journal. Also, record the number of shrimp that are moving and not moving in the data table. 11. After the shrimp have been in the jar for 15 minutes, add 10mL of the sugar dye to each jar. 12. Let the shrimp feed for 10 minutes and then use a blacklight to determine the number of specimen that ate. Record this in the data sheet. At what pH did the acidity of the water begin to affect the Daphina’s ability to feed and ultimately survive? ________ What about the brine shrimp? _________ Graph your data of the Daphina and brine shrimp. You should have four graphs (Daphina: number mobile vs. pH, Daphina: number feeding vs. pH, brine shrimp: number mobile vs. pH, brine shrimp: number feeding vs. pH). Attach the graphs to this write up.

pH

Room Light

UV Light

Moving Not

Moving Glowing Glowing Not

Daphina Control Jar a Jar 1a Jar 2a Jar 3a Jar 4a Jar 5a

Brine Shrimp Control Jar b Jar 1b Jar 2b Jar 3b Jar 4b Jar 5b