Periodic Table Scavenger Hunt

I like students to be comfortable with the periodic as a tool for their use in chemistry, rather than a sheet of information that they memorize.  To keep students up on using the periodic table as a tool, I periodically (no pun intended) ask them to search the periodic table through a scavenger hunt.

I have provided an example below. 

Periodic Table Scavenger Hunt

Hint:                                                                                                   Symbol

1. Start at the element that is a waste product of photosynthesis.            __________  O

2. Add seven AMU’s to the mass                                                         __________  Na

3. Add 26 to atomic number                                                                 __________  Rb 

4. Remain in that period and go to Group IB                                         __________  Ag

5. Go up one period and to the right six groups                                     __________   Br

6. Go to the top of that family                                                                __________  F 

7. Remain in that period and divide the electro-negativity by two            __________  B

8. Add fifty to the atomic number                                                          __________  Cs

9. Go to the element that is a liquid at 25^o C in that period                     __________  Hg

10. Increase the proton count by six                                                      __________  Rn

11. Go to element with the smallest mass in that group                           __________  He

12. Multiply the atomic number by ten                                                   __________  Ca

13. Decrease the proton number five                                                     __________  P

14. Jump to Group IIA in that period                                                    __________  Mg

15. Cut the atomic number in half                                                          __________  C

16. Decrease the mass by 3.0 AMU’s                                                  __________  Be

17. If the element is an even atomic number multiply by 4

      If the element is an odd atomic number multiply by 5                        __________ S

18. Jump up one period. You should be back where you began.            __________ O

While this isn't some earth shattering method of exploring the periodic table, it does provide students with familiarity with the elements, information and terminology necessary to use the periodic table efficiently and effectively. 

Study Card Rings

There are a tremendous amount of great sites online for creating online study aids
(see - quizlet.com), but nothing beats creating and working through your own set of study cards.   Whether it is a full stack of 3 x 5 cards wrapped in a rubber band, or one inch strips cut from 3 x 5 cards and hole punched on a snap key ring.  The actual pocess of creating hand written study cards is a study staple for most students.


I demonstrate this process to my chemistry students when they need to learn the cations and anions that will be used in naming and creating inonic formulas.  To assist students in learning the ions, I create three sets of twenty ions that students are responsible for knowing.  On one side of card stock I have the names of the ions neatly organized in a four card by five card grid created on an excel spreadsheet.  On the opposite side I have the ion formulas with their ionic charge.  On this side I do not put grid lines.  When students cut them out, they only use the name grid lines and that way the lines do not need to match up (for some students this is a distraction if there are random lines on their cards).

I take part of a class period for the students to cut out and punch the cards and place them on a snap ring that I provide for them. It is worth the class time to have students complete the task.  This garauntees every student has the complete set and leaves the student with the idea that they are of some importance since you gave up class time to make the ring card sets.

I have divided the ion sets on three separate color cards and quiz the students on each set separately.  I find that ionic naming, writng balanced chemical equations and stoichiometry all go more quickly and smoother when the students know these ions from memory.


I then suggest that students can create their own study sets in any of their classes by cutting the
3 x 5 cards into one inch strips or they can by the pre-made blank sets at most bookstores or teacher supply stores.

Half the job, is having the correct tools.

Why Do Students Hate Word Problems?

If you surveyed your classroom, how many students would say they like word problems?

20%? 10%? 5%? 

I actually did this in my science classes the other day.  Out of eighty-nine students over three class periods, representing sophomores through seniors, I had six students who claimed to like word problems and another three who did the half arm extension of, they kind of like word problems.  Let us give those students the benefit of the doubt and go with all nine students who claim to like word problems. Nine out of eighty-nine is a whopping 10.1%.  This is just about right for classes in a typical high school, when it comes to their desire to do word problems.

Why is there such a disdain for word problems?  Why do many students even balk at attempting word problems?  Why do word problems provoke fear in the hearts of the adolescent scholar?

As a science teacher, it is an absolute necessity that students work through the process of solving word problems.  I do not have the luxury of simply giving worksheets of repetitious, rote equation based problems.
Whether it is stoichiometry and gas law problems in chemistry or projectile motion or density problems in physics, students must be able to read a word problem, extract the necessary values and determine a method for solving for the unknown?

Over the years I have discussed this dilemma of word problems with the students who have made their way through my classroom. After years of gathering this anecdotal evidence, I have come up with three basic reasons that students avoid, dislike, or fear word problems: The Battle of the Left and Right Brain, The Language Barrier and The Lack of a Plan.

• The Battle of the Left and Right Brain
• Most students are dominant on one side of the brain.  They are either linear, numeric and organized on the leftt side of the brain or they are, artistic, verbal and feeling on the right side of the brain.  Word problems demand that students use both sides of the brain. Heaven forbid, that students use the left side for numbers and the right side for words simultaneously. They might blow a fuse. 
• For a word problem determining how far a person traveling on a plane for a certian period of time would travel at a given rate, students dominant on the left want to know the numbers, the formula and how to find an answer.  Students dominant on the right side of the brain want to know where they are going, what are they wearing and what movie is on the plane.
• Students on the left side of the brain can draw out the numbers but may confuse their significanance because the wording does not make sense.  Students on the right side, can decipher the words but do not necessarily have a purpose for the numbers.  
• A bridge needs to be created to bring the two sides together.  Left sided individuals need to create charts to transfer the numeric values into an organized meaningful process.  Right sided individuals can use diagrams to transfer the words into a meaningful mathematical purpose
• The Language Barrier
• How many word problems have just too much information. Most students get overwhelmed by the sheer wordiness of the word problems.  If their is general discomfort with the math that is only increased by superfluous wording and unfamiliar vocabulary. 
• For example: Johnny walks his shih tzu around his neighborhood every afternoon.  The evening constitutional usually takes about forty five minutes for the two of them to cover the five block trek through the neighborhood.  If the walk consists of one and a half miles, what is the average speed that they walk?
• There are forty nine words in this word problem.  The majority of them are not necessary to solve the problem. Many students would have difficulty with several of the words, shih tzu, constitutional and trek. While it is important to increase vocabulary and integrate science and language, students who have difficulty with word problems will simply avoid this type of  word problem due the seemingly imposing amount of words. 
• Students  must be given the opportunity to develop a sense of success with solving word problems gradually.  With time and greater success, students learn to identify the necessary information and filter out the wording that is unecessary to their problem solving. 
•  The Lack of a Plan
• Students need a problem solving plan.  Not a recipe, but an actual problem solving plan that is generic to all types of problems. 
• I believe the best example of a plan for Problem Solving comes from Rafe Esquith in his book, Teach Like Your Hair is On Fire:

 I have always appreciated the simplicity of this approach, wheter it is for Esquith's grammar school students or AP Calculus students the plan holds true.  I also love the "Put Down Your Pencil" reminder for the brainstorming portion.  Too many students never get started because they don't know where they are going.  This plan forces students to truly develop a means for determining where to start, where to end and the path to choose.  

By providing the proper approach, diffusing their fear and providing a concise plan to solve word problems, most teachers can give students the opportunity to develop success in solving word problems.  They may not ever like them, but they most definitely won't avoid them.

  

Formula Cards

I create formula cards for each of my students to assist them in maniuplating formulas to isolate various variables and help them to solve for each part of a given equation.

Aluminum Foil and Cupric Chloride Labette

The reaction between cupric chloride solution and aluminum foil is a very quick and simple labette to introduce a variety of topics in chemistry.

The reaction provides a very distinct set of observations that allow students to understand evidence that shows a chemical reaction is taking place.  The reaction gives off heat (exothermic reactions), obvious color changes, release of gas (bubbling and condensation), deterioration of the aluminum as it recombines.

The chemical activity is quite unique as there are several reactions taking place.   First the cupric chloride ionizes in the water producing the nice blue color from the copper inons in solution. Most aluminum foil has a layer of aluminum dioxide which reacts with chloride ion to liberate the oxygen and create aluminum chloride. The copper ion reacts with water to form copper hydroxide and release hydrogen. The bubbling is caused by the both hydrogen and oxygen gas which recombine to condense on the cooler surface of the mouth of the test tube. 

I have the students complete this labette multiple times throughout the year as a common thread tying together many different topics in the chemistry curriculum.

Do Your Students Memorize the Periodic Table?

Every truth has four corners: as a teacher I give you one corner, and it is for you to find the other three.

- Confucius -

Frequently, when I mention the fact that I teach chemistry, the first question in response is, "Do you still have them memorize the periodic table?"  This of course is followed by an explanation of how they remember having to memorize all of the elements, the names, the symbols and of course the masses, and how they can no longer remember any of it.

My first inclination is to break into a tirade about my theory of teaching, the Three C's and building a culture of learning.  And, how I do not believe memorization is learning.  How if you memorize something, this does not mean you know what it is or how to utilize it. I would continue that I do not sit down and memorize the recipies in order to cook a meal.  But if I cook the meal well enough a number of times the recipie becomes a part of my knowledge base.  And, that the more times I cook the meal, the less often I need to refer to the recipie.

That is why I give all of my students a periodic table that I have created. I gathered ideas from the other chemistry teachers I work with as well as using information found on the various periodic tables available online and through science distributors like Fisher and Flinn and of courseI looked at a variety of periodic tables in textbooks.  From all of this I designed a periodic table that is a tool that can be used by the students to successfully navigate their year of chemistry.

I allow my students to use their periodic table during all of their work throughout the year, including in class work, quizzes, tests, homework, online assignments, the entire workload for the year.  Invaribly if the students use a this tool enough, the information on the periodic table will become part of their knowledge base and eventually they will use the most repetitive information without referring to the table as the year progresses. Of course, the elements that are used most often like oxygen, carbon, hydrogen, nitrogen sodium and chlorine, are the elements that become part of the students knowledge base.  How often, really, do we use Praseodynium [59 Pr - 140.91amu] or Erbium [ 68 Er - 167.26amu] or in the course of our lives?

Therefore, my answer is a resounding NO!!!! I do not have my students memorize the periodic table.  I do however, expect them to master the use of the periodic table as a problem solving tool throughout their year in chemistry and beyond.

Summer Read - The Disappearing Spoon

This summer I read The Disappearing Spoon (And Other True Tales of Madness Love and the History of the World from the Periodic Table of the Elements), by Sam. Kean.

Kean provides a wonderful new viewpoint of the elements of the periodic table through many different parameters.  He groups the elements in such a way that the reader can easily understand the format concept of the periodic table. Kean introduces the elements of greed Gold, Silver and Platinum as well as those used as weapons of war Bromine, Tungsten and Molybdenum to allow the reader to understand the chemical characteristics, similarities and differences that make these elements functional for each purpose. The book provides enough background of the development of the periodic table from Mendeleev to Seaborg. 

However, one of the better portions of the text involves the explanation of the Big Bang, the lives of stars and how "stuff" gets produced.  Kean's explanation of of "How we are all Star Stuff" and the process of this understanding offers a wonderful bridge for the link between Physics and Chemistry.   

For any science teacher The Disappearing Spoon provides those stories that will help to capture the attention and imagination of students at any level of science. Kean brings such an enthusiasm for the material that the reader is drawn in to reading more and more.  He makes chemistry real by tying the usually vague ideas of elements to very real historical events and people. Kean does an outstanding job of blending the history and science of the elements in everyday language. 

Why We Need to Know Chemistry - DHMO

When am I ever going to use this in real life?
The war cry of the uninformed.

In response to this I share with my students the organization DHMO.org.

A group that explains the ever present danger of Dihydrogen Monoxide.

I also share with my students the hoax played on the City Council of Aliso Viejo when overzealous council members voted to ban this dangerous substance from the city based upon an overwhelming amount of literature touting the very real dangers of this substance. Fortunately, before any reals laws could go into effect, wiser heads prevailed.

The dangerous substance, Dihydrogen Monoxide is of course Water (H2O, Di  2 Hydrogens and Mono for 1 Oxygen). 

DHMO FAQ

For my students the lesson is very clear. That a basic knowledge of as much as possible, is of great value.  You never know when this information will become necessary.

The website and the accompanying data, information and materials outlines the truth of this substance:  can cause burns, is a component in bombs, leads to swelling, excess inhalation can cause death, causes hurricanes, erosion and floods.  The information is accurate and only misleading in the way any information can be manipulated. 

Next time a student begins to whine about when they will ever need to know this, the answer may just be to ask a member of the Aliso Viejo City Council.

 

Alien Juice Bar - Acids and Bases

The Alien Juice Bar tutorial provides a simple and fun way to introduce the characteristics of Acids and Bases including the concepts of pH, pOH, neutralization.

Whether students are killing off aliens by serving them acidic or basic drinks that their constitutions cannot deal with, or they are sorting drinks by their characteristics, students can learn or review the main points of acids and bases.  This tutorial created through UC Berkeley is simplistic enough for middle school while intriguing enough to capture the attention of most high school students.

There are three parts of the tutorial. Part one allows students to learn about pH and pOH by identifying them using cabbage juice.  Phase two allows students to determine which drinks are safe to serve aliens based upon the acidic or basic composition of the monster.  Aliens die when their pH levels are altered. The third phase guides students through the neutralization of pH by mixing acids and bases.

This tutorial is best used on an interactive white board (SMART Board) to involve the entire class in the process of protecting or destroying aliens with basic acidic knowledge.

Elephant's Toothpaste

One of the most exciting classes I conduct in my chemistry classroom is the Elephant's Toothpaste demonstration.  While, this is an old standard and some students have seen it on You Tube or in other science classes, it never fails to capture the student's attention and create opportunities for discussion.

I conduct the demo in a 5 L graduate cylinder. I place the cylinder in an equipment tray placed on a tarp to protect the floor from overflow.

Pour 250 mL of 30% Hydrogen Peroxide (H2O2) to the cylinder and add 1-2 tablespoons of dish soap to the peroxide.  Dawn is preferable, but any dish soap will work.  I drip food coloring down the sides of the cylinder to provide the toothpaste striping. I then add 4-6 grams of Potassium Iodide (KI)  to the solution. Step back and enjoy the reaction, both from the cylinder and the students. 

I do not ask students to complete a lab write-up for this demonstration.  I instead use the opportunity to  discuss rates of reaction. I will have students touch the surface of the cylinder with the back of their hand to feel the heat produced by the reaction and discuss endothermic and exothermic reactions.   There are a multitude of topics that can be discussed from this reaction.

However most important is the discussions that start with the students questioning, why does that happen? Will other types of salt do that? What if we used ....?  Why did we add the soap?  That is when the thinking begins and the learning takes over.
  

Gas Laws and Imploding Cans

Keeping it simple, but providing avenues for learning many concepts is important for both teachers and students.

One lab that I use in my chemistry course is the imploding cans lab to demonstrate gas laws, pressure and temperature relationships. 

Students provide two or three aluminum cans for this lab.
I use a hot plate for safety in my classroom.
Students add about 1-2 mL of water to an aluminum can and place it on a hot plate.
As the can heats up steam will realease out of the opening at the top of the can. 
I discuss why we add water to the can.  The steam is an indicator of when the can is hot enough anad demonstrates how molecules that are hot move rapidly and escape from the container.
When the can is hot enough the student will invert the can in to a trough of room temperature water.
When done properly the students will witness the imploding of the can.
Water will be drawn in to the can due to the low pressure vacuum created.

Discussion points:

• pressure and temperature relationships
• internal and external pressure on the walls of a container
• kinetic molecular theory
• decreasing pressure to create a vacuum
• malleability of metals