Science Lab: What Happens to the ph of Milk if you leave it out of the Refrigerator for Five Days?
|
|
- Anis Bradley
- 7 years ago
- Views:
Transcription
1 Science Lab: What Happens to the ph of Milk if you leave it out of the Refrigerator for Five Days? CONCEPTS: What s a chemical reaction (change)? What happens during a chemical reaction (change)? Do all substances have a chemical change when mixed together? What s the difference between chemical and physical changes? 1. Chemical reactions are different from physical reactions. 2. Chemicals may be classified in many different groups, according to the way they behave. One group of chemicals are known as acids and bases. Acids and bases are the opposite of each other. In between acids and bases are the neutrals, which are neither acidic or basic in nature. Orange juice is an acid (citric acid), drinking water is neutral, and Maalox is a base. 3. ph test paper is one way to measure the acidity or basic nature of a molecule with out having to taste it! 4. Milk has bacteria in in called lactobacillus and coliforms. When milk is allowed to warm up (out of the refrigerator) the coliform bacteria begin to do chemical reactions which make lactic acid, which is sour. We call this soured milk. STANDARDS GLE Observe and measure the simple chemical properties of common substances. GLE 0507.Inq.1 Explore different scientific phenomena by asking questions, making logical predictions, planning investigations, and recording data. GLE 0507.Inq.3 Organize data into appropriate tables, graphs, drawings, or diagrams. GLE 0507.Inq.4 Identify and interpret simple patterns of evidence to communicate the findings of multiple investigations. GLE 0507.T/E.4 Recognize the connection between scientific advances, new knowledge, and the availability of new tools and technologies.
2 EQUIPMENT NEEDED: A clean glass baby food jar (or small 40 ml beaker), milk, ph test strips. STUDENT JOBS: Chemists (everyone takes turns measuring ph); gofer (goes to get equipment and samples); group manager (responsible for insuring that all data is gathered and recorded before the next sample is taken...a chance for that bossy kid to try to develop positive group skills); equipment manager (director of cleaning the equipment...this is good for the hyperactive, wiggly kid!) OPTIONAL EQUIPMENT: 1-13 ph test paper, digital ph tester, ph Scale displayed on Promethean Board. TIME: 10 minutes per day for ONE WEEK PREVIOUS KNOWLEDGE: Not all chemicals have a chemical reaction (change) when they touch other chemicals. Sometimes nothing happens, such as when you drop a glass marble in water. There is no new or different molecule formed-it s still glass and water. Other times when molecules touch, changes occur. These changes are called chemical reactions or chemical change. For example, when a candle is lit, the wax molecule C25H52 is heated and combines with the air to form C25H O2 25 CO H2O. In other words when a wax molecule joins with exactly 38 O2 molecules during burning, things happen! The molecules form different molecules and voila, the wax is reorganized into 25 carbon dioxide molecules and 26 water molecules. None of the atoms were destroyed only changed into new molecules. (This is called the Law of Conservation of Matter and students will learn more about this in coming years.) So, everyone has seen a candle seem to disappear, but it s really turning into everyday carbon dioxide and water. Simple, right? Whenever atoms and molecules reorganize into new groups this is called a chemical reaction (or chemical change). Some common examples are a burning match, a burning candle, a sliced apple turning brown, a rusting nail, baking soda plus vinegar, and a burning piece of paper.
3 So how do scientists know if a chemical reaction has occurred? Remember, not everything is a chemical reaction (change); sometimes it s just a physical change, such as breaking a pencil, tearing paper, or melting ice. Chemists look for the following things to indicate (point out) that there has been a chemical change. THREE WAYS TO TELL THAT A CHEMICAL CHANGE HAS HAPPENED 1. A change of STATE 2. A change of COLOR 3. A change of TEMPERATURE Let s look at each of these briefly. 1. A change of state is the example of the candle. It changes from a solid wax candle into two gases. Baking soda (solid) and vinegar (liquid) turn into an invisible gas. 2. When iodine touches starch it turns black. When oxygen touches copper it turns green. This is why the Statue of Liberty is green! When oxygen touches a nail it turns orange (rust). 3. When some chemicals are mixed they either get hotter or colder on their own. Ever seen a cold pack. Hit it and mix the chemicals together and voila, it gets cold. A hand warmer generates heat when the molecules are mixed. When the chemicals in a match are ground together it gets VERY hot all by itself. These are some general guidelines. Students should learn them in identifying chemical reactions. Ask students to say the 3 ways to tell there s been a chemical reaction when you are talking about chemical reactions (change). This lesson focuses on a chemical change all right, but not a change of color, temperature or state. This milk, and the bacteria in them, will become more acidic over the next five days. There are special chemicals which will help to find certain chemicals and these are called INDICATORS. Chemists use indicators all the time such as testing a swimming pool for chlorine, aquarium water to check for excess acidity or alkalinity (or base). When indicators touch the molecule they react with, a color change occurs. This is much safer that tasting all the chemicals! There is a family of chemicals called the ACIDS and BASES. They are in the same chemical family even though they are opposites of each other. Scientists measure how strong the acids and bases are with something called the ph Scale.
4 The Acids go from 0 to 6. Neutral is 7 on the ph scale. From 8 to 14 are the Bases (also called Alkaline). The strongest ACID is a 0. The strongest BASE is a 14. The increment from number to number is a factor of ten. The weird thing is that a 5 is ten times stronger than a 6. A 4 is ten times stronger than a 5. That would make a 4 on the ph scale one hundred times stronger than a 6! This is a neat math scale. More on this later. There are many indicators for acids and bases. You can even buy a digital ph probe, but for this lesson we will use ph paper 1-13 over a five day period. In this lesson we will test MILK over time to see if it is ACID, NEUTRAL, OR BASE. In each case the indicator will turn a color (which is a sign of a chemical reaction occurring). Will the milk which little Whitney left out become basic, acidic, or not change at all? (See PRODUCTIVE TALK MOVES and STRUCTURING SCIENCE TALK packet. This gives you excellent ways to teach your students to move forward and get past yes/no answers and helps them develop strategies for thinking about the problems.)
5
6 OBJECTIVES: 1. Students will test for acids, neutrals and bases using milk left out at room temperature for a week with 100% accuracy. 2. Students will record the data with 100% accuracy. 3. Students will determine the relative strength of the acids or bases relative to neutral with 100% accuracy. This objective can be done the next day if the teacher has a short class. THE LESSON PREPARATION AND/OR ADVANCED PREPARATION 1. Buy some ph paper strips from Nasco.com. Get some which measure 1-13 ph. 2. Get a cup of milk (or a new, unopened student carton of milk from the cafeteria) THE EXPERIMENT 1. Pour a new, unopened milk carton of fresh milk into two clean glasses (or test tubes). Put an equal amount in each container. 2. Ask students to hypothesize what will happen to the ph of the milk if we left it out? Remind them that ph measures acid, neutral and base. 3. Discuss the following question: Is this question measurable and testable? In a lab? TO DO AN EXPERIMENT IT HAS TO BE TESTABLE? 4. Ask students to form a HYPOTHESIS for what happens to the milk when it sits out. Is it an acid, neutral, or a base? Record the HYPOTHESIS above the DATA Table. 5. Remind (guide their thinking) them that to be a fair test, perhaps there should be two samples of milk, one which remains in the fridge, and one which stays on a counter. Shouldn t they both be tested? (yes. The one which remains in the fridge is what scientists call a CONTROL GROUP) 6. Discuss with students this question: WHAT IS THE INDEPENDENT VARIABLE IS IN THIS EXPERIMENT? (the independent variable is the thing which you are going to do different to one group) What are we doing different to the one milk sample? (leaving it out of the refrigerator to get warm)
7 Normally we don t leave milk out in the room, we keep it in the refrigerator. In this case though, we are leaving the milk out ON PURPOSE. This is called the INDEPENDENT variable. 7. Now, discuss the DEPENDENT VARIABLE is in the experiment. (The dependent variable is the thing which will then be measured.) WHAT IS GOING TO BE MEASURED IN THIS EXPERIMENT? (the ph of the milk each day) 8. Students should tear off a one inch piece of ph paper strip for each glass. Dip the ph paper quickly (just a touch...don t linger!) in the milk and hold it up next to the color key which comes with the ph paper. HINT: it is easier to hold the ph paper strip by a pair of tweezers. Just rinse them off with water and dry them before reusing. Matching the color it turned to the key will tell you the ph number (perhaps 6.7 for milk). Test both milk samples and write the results in the DATA chart. (see below) 9. Repeat step 8 (above) each day for 5 days (MONDAY - FRIDAY. Each day review each of these things: CONTROL GROUP, EXPERIMENTAL GROUP, INDEPENDENT VARIABLE, DEPENDENT VARIABLE. Make little signs which you can hold next to the appropriate group, variable, etc. Write the ph for the warm milk and the refrigerated milk on the data chart each day. (See PRODUCTIVE TALK MOVES and STRUCTURING SCIENCE TALK packet. This gives you excellent ways to teach your students to move forward and get past yes/no answers and helps them develop strategies for thinking about the problems.)
8 HYPOTHESIS: DATA TABLE THE PH OF MILK SOURING DATA TABLE 1 DATE ph of milk in refrigerator ph of milk left out in room CONCLUSION:
9 10. On day five graph the results. I suggest createagraph.com. Below is how the graph will most likely look for the warm milk which was at room temperature. YOU WOULD NEED ANOTHER GRAPH FOR THE CONTROL GROUP (milk in refrigerator). 11.This is a strange scale. It s NOT exactly like a normal number line, is it? 12. Think how powerful battery acid is (see chart at bottom) compared to water (ph 7 neutral)! It s super strong. That means that battery acid (ph 0) is 1,000,000 times stronger than milk (ph 6). Milk has lactic acid in it, making it barely an acid. Unless you let it ferment into yogurt (ph 4.5 to 5). Or it sours (4.7) 13. Have students write a CONCLUSION. Was the hypothesis correct and supported BY DATA?
10 In this lab students learned that a CHEMICAL INDICATOR will turn a color if it comes in contact with a certain type of molecule. Chemists know about dozens of different chemical indicators. These help scientists test for poisons, harmful chemicals, helpful chemicals, and even test for chemicals in the human body. Chemical indicators will show if a person has been drinking alcohol, using marijuana or other illegal drugs, is pregnant, or has diabetes, just to mention a few common indicator tests. So you see, chemical indicators are very useful. The ph papers were indicators. It was a much nicer way to find the ph of the two milk groups than TASTING! Yuk! VARIATIONS AND EXTENSIONS OF THE LESSON Are there other everyday milk product chemicals which students would like to test? Students may want to perform experiments on other milk products, such as yogurt to find out if they contain acid, neutral, or base molecules. QUESTIONS and CONCLUSIONS: 1. What patterns did you see in your results and data? ( the ph number decreased quickly after DAY 3) 2. How might technology help in testing for acid and base molecules? (could use a digital ph probe hooked into your ipad) 3. How does the data chart assist you in making logical predictions and plan addition investigations? (e.g., what might have happened on day 6) 4. Were these physical or chemical changes? Can you justify why these experiments were chemical or physical changes? 5. What TEN substances would you MOST like to test if you had the opportunity? (e.g. stomach acid, tears, the cafeteria food...) 6. Is this an important experiment? Why? Justify your answer with data! (See PRODUCTIVE TALK MOVES and STRUCTURING SCIENCE TALK packet. This gives you excellent ways to teach your students to move forward and get past yes/no answers and helps them develop strategies for thinking about the problems.) 2013 Ronald Boston
11 ph papers which test from 1-11 can be purchased from NASCO science for $ One container will last for years. ph plastic strips from 1-13 can also be purchased from NASCO for $
Chemical Changes. Measuring a Chemical Reaction. Name(s)
Chemical Changes Name(s) In the particle model of matter, individual atoms can be bound tightly to other atoms to form molecules. For example, water molecules are made up of two hydrogen atoms bound to
More informationAcids & Bases Around the House Use a ph indicator to find acids and bases
Use a ph indicator to find acids and bases Description: Visitors predict whether various household solutions are acids or bases, and test their hypotheses using a universal ph indicator. Then, visitors
More informationAcids and Bases. AND a widemouth container of the following solids:
Acids and Bases GOAL To introduce students to acids and bases. MATERIALS: 3 10oz clear plastic cups 1 4 oz. bottle white vinegar - labeled Acid 1 4 oz. bottle of water - labeled Water 1 4 oz. bottle of
More informationProperties of Acids and Bases
Lab 22 Properties of Acids and Bases TN Standard 4.2: The student will investigate the characteristics of acids and bases. Have you ever brushed your teeth and then drank a glass of orange juice? What
More informationSolids, Liquids, and Gases
Solids, Liquids, and Gases nd Intended for Grade: 2 Grade Subject: Science Description: Activities to help students understand solids, liquids, gases, and the changes between these states. Objective: The
More information10-ml Graduated cylinder 40 ml 3% Hydrogen peroxide solution (found in stores) Straight-edged razor blade Scissors and Forceps (tweezers)
Name: Class: Date: Objectives * Measure the effects of changes in temperature, ph, and enzyme concentration on reaction rates of an enzyme catalyzed reaction in a controlled experiment. * Explain how environmental
More informationChapter 6, Lesson 4: Temperature and the Rate of a Chemical Reaction
Chapter 6, Lesson 4: Temperature and the Rate of a Chemical Reaction Key Concepts Reactants must be moving fast enough and hit each other hard enough for a chemical reaction to take place. Increasing the
More informationThe Amazing Elephant Toothpaste! Lesson Overview
The Amazing Elephant Toothpaste! Lesson Overview Students will investigate chemical change. Suggested Grade Levels: 3-8 Standards for Lesson Content Standard A: Science as Inquiry Content Standard B: Physical
More informationNeutralizing an Acid and a Base
Balancing Act Teacher Information Objectives In this activity, students neutralize a base with an acid. Students determine the point of neutralization of an acid mixed with a base while they: Recognize
More informationChemical versus Physical Changes
Chemical versus Physical Changes Permission to Copy - This document may be reproduced for non-commercial educational purposes Copyright 2009 General Electric Company What are physical and chemical changes?
More informationName. Lab 3: ENZYMES. In this lab, you ll investigate some of the properties of enzymes.
Name Lab 3: ENZYMES In this lab, you ll investigate some of the properties of enzymes. So what are enzymes? Enzymes are large protein molecules (macromolecules) They catalyze or speed up chemical reactions
More informationEnzyme Lab. DEFINITIONS: 1. Enzyme: 2. Catalase: 3. Catalyze: 4. Hydrolysis: 5. Monomer: 6. Digestion: BACKGROUND INFORMATION
Enzyme Lab DEFINITIONS: 1. Enzyme: 2. Catalase: 3. Catalyze: 4. Hydrolysis: 5. Monomer: 6. Digestion: BACKGROUND INFORMATION Many living tissues contain the enzyme catalase. This enzyme breaks down hydrogen
More informationWHAT S NEW, CO? Thanks for the opportunity to work with your students. Our goal is to teach developmentally TEACHER S GUIDE
TEACHER S GUIDE WHAT S NEW, CO? GET TO KNOW A CHEMICAL REACTION 2 Thanks for the opportunity to work with your students. Our goal is to teach developmentally appropriate chemistry concepts that support
More informationReview and apply Investigation 5. Let s review Pages 311-312
Review and apply Investigation 5 Let s review Pages 311-312 1. After you tested all the known powders with all the test liquids, describe what you did to identify the unknown powder. Students should have
More informationLaw of Conservation of Matter
Law of onservation of Matter Type of Lesson: ontent with Process: Focus on constructing knowledge though active learning. IP ontent TEKS: 8 Investigate and identify the law of conservation of mass. Learning
More informationTest Bank - Chapter 3 Multiple Choice
Test Bank - Chapter 3 The questions in the test bank cover the concepts from the lessons in Chapter 3. Select questions from any of the categories that match the content you covered with students. The
More informationRemember the best arguments are based on the strongest evidence and can explain why opposing arguments are incorrect.
Magnesium and carbon dioxide Student sheet Burning magnesium in carbon dioxide what will happen? Either the magnesium will go out or it will continue to burn. Which will it be? You will use the evidence
More informationAcids and Bases: Cabbage Juice ph Indicator
Acids and Bases: Cabbage Juice ph Indicator Student Advanced Version Acids and bases are found in a variety of everyday items, including food and drink, medicine, and cleaning products. In this lab, we
More informationProperties of Acids and Bases
Properties of Acids and Bases (Adapted from Flinn Scientific Acid Base Test Kit I #AP4567) Introduction Battery acid, stomach acid, acid rain just a few acids in our everyday life! What does it mean when
More informationFirst Grade Unit A: PHYSICAL SCIENCE Chapter 1: Observing Solids, Liquids and Gases Lessons 1 to 5
First Grade Unit A: PHYSICAL SCIENCE Chapter 1: Observing Solids, Liquids and Gases Lessons 1 to 5 Physical Science Overview Materials (matter) come in different forms. Water can be rain falling (liquid)
More information20.2 Chemical Equations
All of the chemical changes you observed in the last Investigation were the result of chemical reactions. A chemical reaction involves a rearrangement of atoms in one or more reactants to form one or more
More informationBLOWING UP BALLOONS, chemically
BLOWING UP BALLOONS, chemically PRE LAB DISCUSSION: Today we will be using a closed system. A closed system does not permit matter to enter or exit the apparatus. Lavoisier's classic 12-day experiment,
More informationLeavener Lineup. Getting started. How do we use chemical reactions in the kitchen? Hands-on experiment. Year levels 4 5. Curriculum Links.
rise and Shine: what Makes Bread Rise? Lesson 2 Leavener Lineup Year levels 4 5 Curriculum Links Science Science knowledge helps people to understand the effect of their actions (Yr 4, ACSHE062). Solids,
More informationDry Ice Color Show Dry Ice Demonstrations
elearning 2009 Introduction Dry Ice Color Show Dry Ice Demonstrations Publication No. 95016 Add a small piece of solid carbon dioxide to a colored indicator solution and watch as the solution immediately
More informationChemical Reactions & Electricity
THE TEAK PROJECT: TRAVELING ENGINEERING ACTIVITY KITS Chemical Reactions & Electricity Partial support for this project was provided by the National Science Foundation's Course, Curriculum, and Laboratory
More informationAcids, Bases, and ph
CHAPTER 9 1 SECTION Acids, Bases, and Salts Acids, Bases, and ph KEY IDEAS As you read this section, keep these questions in mind: What properties do acids have? What properties do bases have? How can
More informationChapter 5 Student Reading
Chapter 5 Student Reading THE POLARITY OF THE WATER MOLECULE Wonderful water Water is an amazing substance. We drink it, cook and wash with it, swim and play in it, and use it for lots of other purposes.
More informationBay Area Scientists in Schools Presentation Plan
Bay Area Scientists in Schools Presentation Plan Lesson Name Presenter(s) Grade Level 5th The Chemical Workout/Blow it Up Chemistry Graduate Students from the Maimone Group at UC Berkeley Standards Connection(s):
More informationTEACHER ACTIVITY GUIDE
Page 1/5 EXPECTED OUTCOMES TEACHER ACTIVITY GUIDE ROOT BEER PRODUCTION Taken from IFT Experiments in Food Science Series This activity will allow student an opportunity to explore yeast fermentation by
More informationLetter to the Student... 5 Test-Taking Checklist... 6 Next Generation Sunshine State Standards Correlation Chart... 7
Table of Contents Letter to the Student..................................... 5 Test-Taking Checklist.................................... 6 Next Generation Sunshine State Standards Correlation Chart...
More informationSugar or Salt? Ionic and Covalent Bonds
Lab 11 Sugar or Salt? Ionic and Covalent Bonds TN Standard 2.1: The student will investigate chemical bonding. Have you ever accidentally used salt instead of sugar? D rinking tea that has been sweetened
More informationCatalase Enzyme Lab. Background information
Catalase Enzyme Lab Background information Liver and other living tissues contain the enzyme catalase. This enzyme breaks down hydrogen peroxide, which is a harmful by-product of the process of cellular
More informationIDENTIFICATION OF POLYMERS 1998 by David A. Katz. All rights reserved
IDENTIFICATION OF POLYMERS 1998 by David A. Katz. All rights reserved David A. Katz Chemist, Educator, Science Communicator, and Consultant 133 N. Desert Stream Dr., Tucson, AZ 85745 Voice/Fax: 520-624-2207
More informationExperiment 16-Acids, Bases and ph
Definitions acid-an ionic compound that releases or reacts with water to form hydrogen ion (H + ) in aqueous solution. They taste sour and turn litmus red. Acids react with certain metals such as zinc,
More informationPHYSICAL AND CHEMICAL PROPERTIES AND CHANGES
PHYSICAL AND CHEMICAL PROPERTIES AND CHANGES Name Key PHYSICAL PROPERTY CHEMICAL PROPERTY 1. observed with senses 1. indicates how a substance 2. determined without destroying matter reacts with something
More informationWHAT IS THE SCIENTIFIC METHOD?
WHAT IS THE SCIENTIFIC METHOD? A lesson to introduce the application of the Scientific Method to High School Chemistry Students Karen Balbierer CCMR RET I August 15, 2003 Lesson Plan Summary Lesson Subject:
More informationThe Structure of Water Introductory Lesson
Dana V. Middlemiss Fall 2002 The Structure of Water Introductory Lesson Abstract: This is an introduction to the chemical nature of water and its interactions. In particular, this lesson will explore evaporation,
More informationChemical Formulas, Equations, and Reactions Test Pre-AP Write all answers on your answer document.
Name: Period: Chemical Formulas, Equations, and Reactions Test Pre-AP Write all answers on your answer document. 1. Which of the following is a NOT a physical property of hydrogen? A. It is gas C. It is
More informationHow to write a formal lab report correctly. This is based off a lab done in AP biology and all examples are taken from student lab write-ups.
How to write a formal lab report correctly. This is based off a lab done in AP biology and all examples are taken from student lab write-ups. Title: Potato Catalase Enzyme Lab (1 point). * Objective, variables,
More informationO o. Thomas Jefferson National Accelerator Facility - Office of Science Education http://education.jlab.org/
O o b l ekk c What is Oobleck? Can you use THE SCIENTIFIC METHOD AND your senses to solve the mystery of Oobleck? Problem Three liquids are mixed together in a plastic bag. Using your senses (except for
More informationCan Gases Act Like a Greenhouse?
Can Gases Act Like a Greenhouse? Activity 1 Following a discussion that enables student to express what they already know about the greenhouse effect, students conduct a controlled experiment to confirm
More informationTHE STUDY OF THE EFFECT OF DRY ICE ON THE TEMPERATURE OF WATER
THE STUDY OF THE EFFECT OF DRY ICE ON THE TEMPERATURE OF WATER Justin Tunley Cary Academy ABSTRACT: The purpose of this study was to find out how much the temperature of water would change over time after
More informationNAILING RUST. Jim Lowry, fourth-grade teacher Webster Elementary School Pemberville, OH
Jim Lowry, fourth-grade teacher Webster Elementary School Pemberville, OH NAILING RUST Lesson Summary for Grades 3 8 The students are grouped in pairs and go on a walking tour of the school grounds. They
More informationReturn to Lab Menu. Stoichiometry Exploring the Reaction between Baking Soda and Vinegar
Return to Lab Menu Stoichiometry Exploring the Reaction between Baking Soda and Vinegar Objectives -to observe and measure mass loss in a gas forming reaction -to calculate CO 2 loss and correlate to a
More informationPhysical and Chemical Changes
Physical and Chemical Changes Jana Barrow West Point Jr. High 2775 W 550 N 801-402-8100 West Point, UT 84015 jbarrow@dsdmail.net Eighth Grade Integrated Science Standard I: Students will understand the
More informationExperiment 8: Chemical Moles: Converting Baking Soda to Table Salt
Experiment 8: Chemical Moles: Converting Baking Soda to Table Salt What is the purpose of this lab? We want to develop a model that shows in a simple way the relationship between the amounts of reactants
More informationVANDERBILT STUDENT VOLUNTEERS FOR SCIENCE. Acids and Bases. Fall 2012
VANDERBILT STUDENT VOLUNTEERS FOR SCIENCE Acids and Bases Fall 2012 GOAL: To introduce students to acids and bases. MATERIALS 3 10oz clear plastic cups 1 4 oz. bottle white vinegar - labeled Acid 1 4 oz.
More informationChapter 3 Student Reading
Chapter 3 Student Reading If you hold a solid piece of lead or iron in your hand, it feels heavy for its size. If you hold the same size piece of balsa wood or plastic, it feels light for its size. The
More informationTESTING DRY ICE IN DIFFERENT LIQUIDS. Aditya S. Cary Academy ABSTRACT
TESTING DRY ICE IN DIFFERENT LIQUIDS Aditya S Cary Academy ABSTRACT The purpose of this experiment was to see how dropping dry ice into different liquids affect the mass and temperature of the dry ice.
More information$$059?7=V$HRIR$W$#49;$!9PP5=>$;<$)9>>$?L@7=V$9$%456789:$0598;7<=$7=$9$ %:<>5?$,K>;563
$$059?7=V$RIR$W$#49;$!9PP5=>$;>$?L@7=V$9$%456789:$0598;7;563 D$&&'"(*B$)7 Did you know that when you play with glow sticks, you are watching a chemical reaction in a closed system?
More informationVitamin C Content of Fruit Juice
1 Vitamin C Content of Fruit Juice Introduction Vitamin C Vitamins are organic compounds that have important biological functions. For instance, in humans they enable a variety of enzymes in the body to
More informationSyllabus OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral
Chemistry: 9. Acids and Bases Please remember to photocopy 4 pages onto one sheet by going A3 A4 and using back to back on the photocopier Syllabus OC18 Use litmus or a universal indicator to test a variety
More informationMOLES, MOLECULES, FORMULAS. Part I: What Is a Mole And Why Are Chemists Interested in It?
NAME PARTNERS SECTION DATE_ MOLES, MOLECULES, FORMULAS This activity is designed to introduce a convenient unit used by chemists and to illustrate uses of the unit. Part I: What Is a Mole And Why Are Chemists
More informationUnit 1 - Pure Substances and Mixtures Chapter 2: Solutions
2.1 Solutes & Solvents Vocabulary: Unit 1 - Pure Substances and Mixtures Chapter 2: Solutions solvent the larger part of a solution - the part of a solution into which the solutes dissolve solute the smaller
More informationCHEMICAL FORMULAS AND EQUATIONS
reflect Imagine that you and three other classmates had enough supplies and the recipe to make one pepperoni pizza. The recipe might include a ball of dough, a cup of pizza sauce, a cup of cheese, and
More informationTeachers Notes BATH BOMB FACTORY
Teachers Notes BATH BOMB FACTORY BATH BOMB FACTORY 2 BATH BOMB FACTORY INTRODUCTION BATH BOMB FACTORY is a fun activity that promotes scientific thinking. It allows children to explore materials and find
More informationANSWER KEY. Acids, Bases, and Solutions. Chapter Project Worksheet 1 1. Answers will vary. Sample: cherries, blueberries,
Chapter Project Worksheet 1 1. Answers will vary. Sample: cherries, blueberries, and grass 2. Answers will vary. Sample: Cut 5 g of cherries into small pieces and place in blender. Blend for two minutes,
More informationMixing Warm and Cold Water
Mixing Warm and Cold Water A Continuing Investigation of Thermal Pollution By Kevin White 1 Context: This lesson is intended for students conducting an ongoing study of thermal pollution. Perhaps, students
More informationIntroduction. ph = log [H + ]
Visualizing ph 2010, 1992 by David A. Katz. All rights reserved. Permission granted for classroom use. All reproductions must include original copyright. David A. Katz Chemist, Educator, Science Communicator,
More information19.1 Bonding and Molecules
Most of the matter around you and inside of you is in the form of compounds. For example, your body is about 80 percent water. You learned in the last unit that water, H 2 O, is made up of hydrogen and
More informationph Measurements of Common Substances
Chem 100 Section Experiment 10 Name Partner s Name Introduction ph Measurements of Common Substances The concentration of an acid or base is frequently expressed as ph. Historically, ph stands for the
More informationLesson 4. Temperature change
54 Lesson 4 Temperature change T E A C H E R G U I D E Lesson summary Students meet scientist Jason Williams, an industrial chemist who designs the materials and processes for making solar cells. He explains
More informationChemical Reactions Practice Test
Chemical Reactions Practice Test Chapter 2 Name Date Hour _ Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The only sure evidence for a chemical reaction
More informationShampoo Properties Evaluation General Science
/ 10 Shampoo Properties Evaluation General Science Name It is difficult to obtain exact information on the formulation of commercial shampoos. These facts are held by the manufacturer to protect their
More informationChapter 2, Lesson 5: Changing State Melting
Chapter 2, Lesson 5: Changing State Melting Key Concepts Melting is a process that causes a substance to change from a solid to a liquid. Melting occurs when the molecules of a solid speed up enough that
More informationEnzyme Pre-Lab. Using the Enzyme worksheet and Enzyme lab handout answer the Pre-Lab questions the pre-lab must be complete before beginning the lab.
Enzyme Pre-Lab Using the Enzyme worksheet and Enzyme lab handout answer the Pre-Lab questions the pre-lab must be complete before beginning the lab. Background: In this investigation, you will study several
More informationOrder of the Weather Experiments
Order of the Weather Experiments 1. Staying Dry Towel in bottle--student i. Magic Air Pushing the stick down-- Student ii. Air Power Water in funnel--teacher 2. Tipping the Scale Weighing air--student
More informationChapter 16: Tests for ions and gases
The position of hydrogen in the reactivity series Hydrogen, although not a metal, is included in the reactivity series because it, like metals, can be displaced from aqueous solution, only this time the
More informationThermodynamics. Thermodynamics 1
Thermodynamics 1 Thermodynamics Some Important Topics First Law of Thermodynamics Internal Energy U ( or E) Enthalpy H Second Law of Thermodynamics Entropy S Third law of Thermodynamics Absolute Entropy
More informationDesigning An Experiment Using Baking Soda and Vinegar
Designing An Experiment Using Baking Soda and Vinegar Introduction: Kinetics is the study of chemical reaction rates. It is the study of how fast different chemicals react with one another to form new
More informationLearning outcomes. Students will be able to:
Learning structure of the lesson The big picture This lesson is designed to exemplify an argumentation approach to practical work, using a predict-observe-explain framework. Students often think that some
More informationHeat and Temperature: Teacher s Guide
Heat and Temperature: Teacher s Guide Grade Level: 6-8 Curriculum Focus: Physical Science Lesson Duration: Two class periods Program Description Humans have always been feverish about temperature. But
More informationChemistry 101. Chemistry Experiments for the Home Acidity Determination Using Indicators
Chemistry 101 Chemistry Experiments for the Home Acidity Determination Using Indicators I. Objective: To determine the acidity of a variety of common substances by the use of indicators. To prepare your
More informationLesson Plan: How Do We Know What is Healthy Water?
Lesson Plan: How Do We Know What is Healthy Water? Estimated Time: 1-3 days ph /Chlorine / Hardness State Standards taught and addressed Grade 8: Standards Taught (and evaluated at end of lesson) Science
More informationCREATE SIOP Science Project: Lesson 12 Chemical Reactions SIOP LESSON PLAN. Length of lesson _75-90 minutes (two periods) _
CREATE SIOP Science Project: Lesson 12 Chemical Reactions LESSON TOPIC: Chemical Interactions UNIT FOCUS: Chemical Reactions SIOP LESSON PLAN Lesson # 12_ Length of lesson _75-90 minutes (two periods)
More informationWhat s in a Mole? Molar Mass
LESSON 10 What s in a Mole? Molar Mass OVERVIEW Key Ideas Lesson Type Lab: Groups of 4 Chemists compare moles of substances rather than masses because moles are a way of counting atoms. When considering
More informationPartnerships Implementing Engineering Education Worcester Polytechnic Institute Worcester Public Schools Supported by: National Science Foundation
Temperature: 6.D.3 Temperature and Heat Transfer Grade Level 6 Sessions Seasonality Instructional Mode(s) Team Size WPS Benchmarks MA Frameworks Key Words 1 Approximately 1.5 hours (10 minutes for cleanup)
More informationEXPERIMENT 20: Determination of ph of Common Substances
Materials: ph paper and color chart (ph range 3 to 12) or ph meter distilled water white vinegar household ammonia (or baking soda) spot plate test or 3 small test tubes stirring rod solutions / fruits
More informationOxygen Give and Take. Correlation to National Science Education Standards
Chemistry and Environmental Sciences Oxygen Give and Take Summary This is a series of three activities followed by a worksheet. The concepts taught include gas production (O 2 and CO 2 ), chemical reactions,
More informationStudents will investigate the characteristics of electromagnetism and then use what they learn to plan and conduct an experiment on electromagnets.
Electromagnetic Power! Lesson Overview Students will investigate the characteristics of electromagnetism and then use what they learn to plan and conduct an experiment on electromagnets. Suggested Grade
More informationExploring Energy. Third - Fifth TEKS. Vocabulary
Exploring Energy Third - Fifth TEKS Third Grade: 3.5A, 3.5B, 3.5C, 3.6A Fourth Grade: 4.5A, 4.5B, 4.6A, 4.6B, 4.6C Fifth Grade: 5.5A, 5.6A, 5.6B Vocabulary conductor, convection, conversions, electrical,
More informationsciencemuseumoutreach Kitchen Science 1 Demonstrations to do at home
sciencemuseumoutreach Kitchen Science 1 Demonstrations to do at home The Creative Canal Project (CCP) is part of the Science Museum s Outreach Department, which works with teachers, students, families
More informationLab 25. Acid-Base Titration and Neutralization Reactions: What Is the Concentration of Acetic Acid in Each Sample of Vinegar?
Lab 25. Acid-Base Titration and Neutralization Reactions: What Is the Concentration of Acetic Acid in Each Sample of Vinegar? Introduction Vinegar is basically a solution of acetic acid (CH3COOH). It is
More informationSample Liver Enzyme Lab
Sample Liver Enzyme Lab Design Aspect 1: Research Question This lab will be driven by the research question, Do changes in temperature have an effect on the activity of the enzyme catalase? Pearson Baccalaureate:
More informationCatalytic Activity of Enzymes
Catalytic Activity of Enzymes Introduction Enzymes are biological molecules that catalyze (speed up) chemical reactions. You could call enzymes the Builders and Do-ers in the cell; without them, life could
More informationIII. BACKGROUND KNOWLEDGE
Chemical Bonds and Reactions (Water) Grade Level: 7 (Applied Technology) Presented by: James Rubright, Three Oaks Middle School, Fort Myers, Florida Length of Unit: Ten Daily Lessons and Activities I.
More informationCHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS
CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS Purpose: It is important for chemists to be able to determine the composition of unknown chemicals. This can often be done by way of chemical tests.
More informationChemistry Worksheet: Matter #1
Chemistry Worksheet: Matter #1 1. A mixture (is/is not) a chemical combining of substances. 2. In a compound the (atoms/molecules) are (chemically/physically) combined so that the elements that make up
More informationCatalase. ***You will be working with hot water, acids and bases in this laboratory*** ****Use Extreme Caution!!!****
AP BIOLOGY BIOCHEMISTRY ACTIVITY #9 NAME DATE HOUR CATALASE LAB INTRODUCTION Hydrogen peroxide (H 2 O 2 ) is a poisonous byproduct of metabolism that can damage cells if it is not removed. Catalase is
More informationDETERMINING THE ENTHALPY OF FORMATION OF CaCO 3
DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3 Standard Enthalpy Change Standard Enthalpy Change for a reaction, symbolized as H 0 298, is defined as The enthalpy change when the molar quantities of reactants
More informationMelting ice Student sheet
Melting ice Student sheet Predict Which ice cube will melt first? Observe Describe what you saw happen. Why? (Give a scientific explanation) Questions to think about: Why does ice melt? Why might one ice
More informationACIDS AND BASES SAFETY PRECAUTIONS
ACIDS AND BASES Mild acids and bases are used in cooking (their reaction makes biscuits and bread rise). Acids such as those in our stomachs eat away at food or digest it. Strong acids and bases are used
More informationChapter Test A. States of Matter MULTIPLE CHOICE. a fixed amount of STAs2 a. a solid. b. a liquid. c. a gas. d. any type of matter.
Assessment Chapter Test A States of Matter MULTIPLE CHOICE Write the letter of the correct answer in the space provided. 1. Boyle s law explains the relationship between volume and pressure for a fixed
More informationMixtures and Pure Substances
Unit 2 Mixtures and Pure Substances Matter can be classified into two groups: mixtures and pure substances. Mixtures are the most common form of matter and consist of mixtures of pure substances. They
More informationA Study of Matter. Video Notes
A Study of Matter Video Notes In this lesson you will: Define physical property, chemical property and chemical change. Describe the phases of matter. Label properties as physical or chemical. Label changes
More informationClassifying Matter. reflect. look out!
reflect Do you know what air, water, and an apple all have in common? They are all examples of matter. Matter is a word we use a lot in science. It means stuff. All of the stuff in the world that has mass
More informationHousehold Acids and Bases
Household Acids and Bases GRADE LEVEL INDICATORS Experiment Demonstrate that the ph scale (0-14) is used to measure acidity and classify substances or solutions as acidic, basic, or neutral. 21 Develop
More informationSugar Makers. Real-world Connection: Energy harnessed by photosynthesis powers ecosystems, machines, and even our own bodies.
Sugar Makers Principle of Plant Biology #1 Plants contain the same biological processes and biochemistry as microbes and animals. However, plants are unique in that they have the ability to use energy
More informationUnit 5 Photosynthesis and Cellular Respiration
Unit 5 Photosynthesis and Cellular Respiration Advanced Concepts What is the abbreviated name of this molecule? What is its purpose? What are the three parts of this molecule? Label each part with the
More informationCLEANING WATER. Student Section
National Aeronautics and Space Administration CLEANING WATER Student Section Student Name This lesson challenges you to create and test a water filtration system. During this lesson, you will design and
More information