Showing posts with label K-12 STEM teachers. Show all posts
Showing posts with label K-12 STEM teachers. Show all posts

Tuesday, August 19, 2014

Are Kangaroo Farts Eco-Friendly?

In the latest issue of Fisher Science Education's Headline Discoveries, Samba Lampich goes where few will go: farts. That's right, Lampich talks about the off-putting pungent smells that normally linger much longer than you'd want them to whether they come from a pet or a loved one. 

What we didn't expect to encounter as we made our way through Lampich's smelly piece, though, was that unlike other ruminants, kangaroo farts have been known to contain about 80% less methane than cows. Methane is the most potent of greenhouse gases (GHG) and according to the Food and Agriculture Organization (FAO) of the United Nations, the total emission from global livestock is 7.1 Gigatonnes of CO2  equivalent per year, which represents 14.5% of all anthropogenic GEG emissions. That being said, the amount of methane in kangaroo farts (or lack there of, for that matter) is impressive.

Lampich talks about microbiologist Scott Godwin of Queensland Department of Agriculture, Fisheries and Forestry in Brisbane, Austrailia, and his colleagues, who investigated the microbes in kangaroos' digestive tracts and published their findings in the March 13 issue of The ISME Journal. 

While most animals create carbon dioxide and hydrogen when they digest their food, animals like cows and sheep have microbes in their guts called methanogens that create methane. After looking at three wild eastern gray kangaroos, Godwin and his team found some methane-making microbes in the kangaroos' samples, but they also found  other active microbes including acetogens. These microbes take in carbon dioxide and hydrogen to produce acetate, which becomes a source of energy for the kangaroos.

Now that researchers know why kangaroos produce less methane, they need to figure out if implanting kangaroo microbes, which included the acetogens, into livestock would reduce their methane production. This would help reduce global warming!

Check out Lampich's full article, complete with a vocabulary list and factoids, along with the rest of the most recent issue of Headline Discoveries here.

Tuesday, July 29, 2014

Let's Rock!: Build a Bottle Rocket This Summer

Have you ever wondered what launches a rocket? Would you ever guess that it was something as simple as built up pressure? Well try it our for yourself and make a bottle rocket in your backyard this weekend!

Here's what you'll need:
  • An empty plastic bottle
  • Cardboard made into a cone and 4 fins
  • A cork
  • A pump with a needle adapter
  • Water
Now let's get started:
  1. Push the needle adapter of the pump through the cork and make sure it goes all the way through. To do this you may have to trim the cork down a little bit.
  2. Take your cardboard cone and fins and apply them to the bottle. (The cone at the top and the four fins at the bottom, so that the bottle resembles a rocket.)
  3. Fill the bottle with water until it's about a quarter full and then push the cork in tightly.
  4. Attach the pump to the needle adapter. If your bottle rocket won't stand up on it's own with the fins you made, rest it on a table, but if you make strong fins, you should fine and your bottle should stand up on its own.
  5. Pump air into the bottle and prepare for lift off! Make sure that everyone is standing away from the bottle as it will go up in the air with force after just a few seconds.


So what about the science? Check out Science Spark's explanation.

Wednesday, June 18, 2014

Summer Science: Magic with Milk

Beat the heat with this great summer science experiment! Grab these typical household items and start a journey full of exploration and discovery. In this popular Dr. Mad Science experiment, you and your young scientists will observe how milk reacts with food coloring and soap.

Here's what you'll need:
  • Milk (it is recommended that you use 2%)
  • A bowl
  • Food coloring
  • Q-tips
  • Dish Soap (it is recommended that you use Dawn)
Now let's get started:
  1. Start by filling the bowl with milk and waiting for all the bubbles to go away.
  2. Put a large amount of food coloring in the center of the milk.
  3. Take Q-tips and dip them into the dish soap. Then put them in the middle of the bowl for 15 seconds.
  4. Watch as the food coloring expands on the surface of the milk.
So what about the science? Well here it is: milk contains protein and really small amounts of fat in it. Both proteins and fat are sensitive to chemical changes. The chemicals in the dish soap weaken the chemical bonds that hold the protein together in the milk solution and the food coloring allows us to visually see the changes in the protein molecules. Likewise, the soap molecules cause the fat in the milk to mix and swirl until the fat has been distributed across the entire amount of the milk.

Watch Dr. Mad Science do it!

Tuesday, April 8, 2014

Enrollment in STEM Booms Since Recession

Good news for STEM advocates: a new study suggests that undergraduates at four-year institutions have become much more likely to study STEM fields, especially engineering and biology.

As reported by Scott Jaschik for Inside Higher Ed, the new study suggests that STEM enrollments are growing while professional field enrollments (especially business and education) are shrinking, contrary to what public discussion might suggest.

The new research was presented at the annual meeting of the American Educational Research Association last weekend and is by professor of sociology at the University of Pennsylvania Jerry A. Jacobs and professor of education at the University of California at Los Angeles Linda Sax.

Though much of the data normally discussed on student enrollment patterns is pulled from the National Center for Education Statistics, this new study is based in large part on the "freshman survey" conducted annually by UCLA on a national pool of freshman at four-year institutions. Jaschik points out that in their paper, Jacobs and Sax state that this data set enables them to spot trends much earlier than is possible with the federal database, since that information is based on graduation (which comes later than enrollment) and because government cuts have led to delays in federal data.

Using data collected by UCLA, Jacobs and Sax write that enrollment in STEM fields steadily declined between 1997 and 2005, hitting a low in 2005 of 20.7 percent. While modest gains appeared in 2006 and 2007, significant increases started to show up in 2008. The percentage of freshmen planning to major in STEM fields increased from 21.1 percent in 2007 to 28.2 percent in 2011, just as the recession was prompting students and families to focus on job opportunities in various fields. That represents a 48 percent increase in just a few years.

Read Jaschik's entire article to find out how the growth in STEM fields played out across the subjects and if the gender gap so commonly discussed in conjunction with STEM fields changed during the boom.

Tuesday, January 28, 2014

Design Your Future with the STEM Career Lab!

Do you want to explore STEM careers and find out which one you think is for you? Then this is the resource for you! Stemcareerlab.org was designed to help high school students explore future STEM career fields.

Today's STEM professionals create virtual worlds, design amazing machines, invent new materials, construct earth-friendly buildings and engineer cutting-edge air vehicles. And that's just to name a few! Through the collection of videos on stemcareerlab.org, students can hear from STEM professionals about their educational pathway, what it is they love about their jobs, and how they really do use the science and math they learned in high school. 

Professions on the website include advanced manufacturing and materials, aerospace engineering, agricultural engineering, architecture, biomechanical engineering, biomedical engineering, construction management, electrical engineering, human performance, systems engineering, virtual reality design, and water resource management. 

Check out a video today and start planning your STEM future!

Wednesday, November 27, 2013

Thanksgiving Science: Why You Really Can't Blame the Bird

As you gear up for Thanksgiving, everyone normally pictures something along these lines: Indulge in a big meal centered on a turkey prepared to your liking, move things to the couch and watch football while you eat dessert and then start nodding off before the 7:30 game even kicks off. It's not breaking news that catching the holiday bug can be exhausting, but blaming your afternoon nap on the turkey is all wrong, say scientists.

NBC News reports that sure, turkey contains tryptophan, an amino acid that produces the brain chemical serotonin, known to cause calm and sleepiness. But the amount of tryptophan in turkey is extremely small, and other amino acids commonly in the Thanksgiving meal actually block tryptophan's entry to the brain!

Scientists say that the infamous Thanksgiving nap has more to do with missing out on sleep, drinking alcohol and working hard to digest the carb-loaded meal than it does the turkey. So turkeys everywhere urge you: stop blaming your lazy afternoon and casual post-meal nap on the them.

For more bites of Thanksgiving science to chew on, including how science "built" a better turkey and how science created a better balloon, check out NBC News.

Wednesday, October 2, 2013

Discover the Microscopic World!

You have a microscope and you've gone through the basics and know how to use it, but you don't have a lot of stuff to examine - or so you think. You'd be surprised at the the number of things just laying around your house that become fascinating specimen when magnified and explored through the lens of your microscope. Here are some of our favorite suggestions:
  1. Fibers: Pull out a few individual fibers from different fabrics like cotton, nylon, rayon, silk, wool, etc. Place them one-by-one on the center of a slide and add a drop of water and a cover slip. Examine each fiber under different light and objective settings to see what you discover.
  2. Hair: Noticing the differences in hairs can be one of the coolest things to do with your microscope. Examine different types of hair - naturally curly, permanently waved, blonde, brown, red, grey, etc. Check out the difference when the hair is void of oils after dipping your specimen strand in alcohol or soapy water. Compare human hair to that of other mammals.
  3. Paper: Place the torn edge of a piece of paper under the microscope. Light it from above with a flashlight or lamp and then focus in on the torn edge. What do you see? Compare different types of paper.
  4. Crystals: Place a few crystals of table salt (NaCl) or sugar on a slide and view after adjusting for the best illumination. (Remember: too much light will not reveal much detail.) Slip a piece of black paper beneath the crystals and use side lighting from a lamp or flashlight. What do the crystals look like now?
  5. Currency: Examine a dollar bill under various magnifications of the microscope. Compare the fine detail of the engraving process to that of paper play money. We took a look at some currency ourselves - take a look at our picture above!
  6. Colored Pictures: Look at a colored postcard or picture from a magazine. What are you surprised to see?
  7. Pond Water: Stationary water like pond water is always one of the favorite sources of microscopic organisms for many people. You will find some incredible changes in the kinds of organisms present over several weeks or months.
For lesson plans and more formal activities that you can do with your microscope, click here.

Friday, September 27, 2013

Kitchen Experiment: Magic Ketchup

What would your little minds think if you told them that they could make a pack of ketchup float and sink at their command while it was sealed inside a one liter bottle? I know, they'd tell you that that was impossible! Lucky for you, you can work with them to prove them wrong and teach them a little about buoyancy and density in the process. Sounds like a win-win to me.

So let's get started! Here's what you'll need:
  • 1 liter plastic bottle
  • Ketchup packet from a fast food restaurant
  • Salt (using Kosher salt will keep your water from become foggy)
Here's what you'll do:
  1. Remove all labels from the plastic bottle and fill it to the top with water.
  2. Add the ketchup pack to the bottle.
  3. If the ketchup packet floats, you're ready to move on to step four. If the ketchup packet doesn't float and starts to sink, skip to step five.
  4. For the floating ketchup packet, simply screw the cap on the bottle and squeeze the sides of the bottle hard. If the ketchup sinks when you squeeze it and floats when you release it, you're in business and ready to show off your magical powers! If it doesn't sink when  you squeeze the bottle, try a different ketchup packet or a mustard or soy sauce packet.
  5. If the ketchup packet sunk when you put it in the bottle, add around 3 tbsp. of salt to the bottle and shake it until the salt dissolves.
  6. Continuing adding sale a few tablespoons at a time until the ketchup packet is just barely floating at the top.
  7. Once it's consistently floating, make sure the bottle is filled to the top with water and then cap it tightly.
  8. Now squeeze the bottle. The magic ketchup should sink when you squeeze the bottle and float up when you release it. If you get really good, you can get it to stop in the middle of the bottle!
So how does it work? What' behind the magic? This entire experiment revolves around two things: buoyancy and density. Buoyancy describes whether objects float or sink and density deals with the amount of mass in an object. Adding salt to the water adjusted its density and got the ketchup packet to float. There is a little bubble inside of the ketchup packet and, since we know bubbles float, this bubble is what keeps the packet from sinking. But when you squeeze the bottle, you put pressure on the packet that results in  the bubble getting smaller and the packet becoming more dense. Thus, it sinks. When you release the pressure the bubble expands, the packet becomes less dense and more buoyant and floats back to the top.

To take this experiment to the next level, try answering these questions:
  1. Do different food packets (ketchup, mustard, soy sauce, relish, mayo, etc.) have the same density?
  2. Does the temperature of the water affect the density of the ketchup packet?
  3. Does the size of the bottle affect how much you have to squeeze to get the packet to sink?

Monday, September 23, 2013

Zombies & STEM: Coming to a Classroom Near You

Photo courtesy of STEM Behind Hollywood
When all else fails, turn to the undead, right? For many teachers trying to boost student interest in STEM, that's exactly right. Thanks to a new program created by the National Academy of Science and Texas Instruments, teachers now have STEM lessons based on zombies, superheroes, space and forensics to present to their middle and high school students. It looks like the undead could be exactly what the suffering subjects need to bring them back to life.

I know what you're thinking: the concept is too far-fetched to work. Maybe not. STEM Behind Hollywood begins their four-part activity with zombies and a hypothetical virus infecting humans. As reported in Forbes last week, in the part of the activity, students can observe a zombie's behavior and deduce that something is wrong with the cerebellum, the part of the brain that controls walking. From there, they can work to understand how a healthy brain works and reverse engineer a zombie brain.

STEM Behind Hollywood is hoping for what all STEM initiatives have hoped for in recent years: a boost in curiosity and excitement about STEM careers. The Department of Labor estimates a 17 percent jump in these fields by 2018, so the fact that teen interest among them is declining is hard to hear.

Nonetheless, the new program seems to be staggering in the right direction. STEM Behind Hollywood is available to teachers and students on a free TI-Nspire software trial, but those who purchased the graphing calculator get the software included at no extra charge. There's also an iPad app.

After going live on Aug. 8, the program has already seen 2,300 downloads and the zombie program is underway to go live later this fall with other developed themes. Texas Instruments is in works to extend the program through 2014.

To read more about the program, what else is our there like it and to see commentary from the president of Texas Instruments and educators implementing STEM Behind Hollywood in their classroom, check out Emily Canal's full report. 

Wednesday, September 18, 2013

Research Shows Men & Women Do See Things Differently

We all know men and women think differently. Who's judgement is normally better - well, that's up for debate. Nonetheless, recent research suggests that opposite genders really do see things differently - particularly when it comes to colors.  In this month's issue of Headline Discoveries, Joe Giacobello reported that women are better at distinguishing among subtle color differences, while men have greater sensitivity to fine detail and rapidly moving, distant objects.

So let's get down right brainy. Scientists say that there are high concentrations of androgen - the male sex hormone receptors - in the visual cortex of the brain, which is responsible for processing images and explains their sensitivity. 

When it comes to knowing colors, women are who you want to talk to. Isreal Abramov and his research team at CUNY's Brooklyn College conducted a series of visual tests on men and women at both the high school and college level. Among other things, Abramov and his team found that women detected tiny differences between yellows that looked the same to men.

So why do men and women see differently. Can it really all be attributed to hormones in the brain? Not exactly. As stated in Headline Discoveries, a possible, but highly speculative explanation for why the sexes see different is for evolutionary advantages. Back in the hunter-gatherer societies, the males needed to see predators or prey in the distance while women had to detect subtle color differences while scouring for edible plants. An interesting perspective id we do say so ourselves.

To read the full article and to check out follow up questions that can be used for classroom discussion, click here.

Tuesday, September 10, 2013

STEM Interest Among Teens Declining?

CBS News reported yesterday that STEM interest among teens is actually declining. This may seem strange given the economy's current state and the difficulty finding a job many members of the younger generation are facing, but experts at the Partnership for a New American Economy project say that there will be a shortfall of 230,000 qualified advanced-degree STEM workers by 2018.

At a time when most buzz about STEM and the initiatives in place to make it more exciting and relevant in today's schools is positive, this comes as a total downer. As stated in the CBS News report, the Partnership for a New American Economy project's Junior Achievement USA and ING U.S. Foundation teamed up to survey 1,025 teens about their career plans. This is the 12th year that they have conducted the survey, and nearly half of the students ranked STEM and medical-related fields as their top choice. Forty-six percent sounds encouraging, but that is a 15 percent decline from the 2012 survey, when 61 percent of students considered STEM their top choice.

So what's happening? Where is the disconnect between efforts being made to make STEM the go-to choice for student interest and actual student interest? Are U.S. students just simply more interested in other fields than they are STEM fields?

As CBS explains, regardless of whether there is a shortage, the first step in developing a deeper American talent pool is bolstering student interest in STEM fields. The question now: how are we going to do that?

It appears we may to go back to the drawing board, reevaluate current initiatives and efforts and implement some changes.

Check out the full CBS News report for detailed commentary on the topic and more information.

Friday, September 6, 2013

'Science' Moving on Up as Most Important School Subject

There's good news for all you science lovers out there: a new Gallup poll finds that three times as many Americans now say science is the most valuable school subject (MVS) than did so more than a decade ago. As reported by LiveScience on Mashable, science bumped out history for the third spot behind No. 1 math and No. 2 language arts as the school subject that has been most valuable to Americans' lives. This is exciting news!

In the new Gallup poll conducted earlier this month (Aug. 7-11), 12 percent of respondents mentioned "science/physics/biology" as the MVS. In the same poll conducted in 2002, a mere 4 percent felt the same way.

Interestingly enough, it appears that education and gender played a part in affecting people's answers. Respondents who had high levels of education were less likely to choose math as the MVS. Likewise, men were more apt than women to give math the top spot - 40 percent versus 28 percent, respectively. Men were also more likely than women to choose science as most valuable.

The poll results are based on phone interviews with a random sample of 2,059 Americans, ages 18 and over, from all 50 U.S. states and Washington D.C. Results were weighted so they were nationally representative. Further, respondents were allowed to look back at their entire education when gauging the value of subjects, including elementary all the way through postgraduate school.

For more information on the poll results and to see specific excerpts and statements from the Galllup statement, check out the Mashable article. The importance of science is making a name for itself and we're moving in the right direction!

Tuesday, September 3, 2013

Pass Rate on Math & Science AP Tests Rise

In an article published by McClatchy last week, Renee Schoof reported that the pass rate on rigorous Advanced Placement tests went up by 72 percent last year at high schools that took part in a National Math and Science Initiative program that trains teachers and gives students extra help on Saturdays.

The proof is in the puddin'. That being said, with statistics like the one above, what could possibly be argued about the initiative other than it's working for U.S. students? The article elaborates and states that the program has been especially helpful in boosting success for girls and minority students - groups that initiative CEO Sara Martinez Tucker says have been under-represented in advanced math and science classes.

Supporters, participants and teachers involved in the initiative's training says that the program raises expectations. It looks as though when teachers are stepping up their game in the classroom, students feel inclined to do the same. Why the program hasn't made its way on to more campuses is practically shocking.

Last year. the initiative was in place in 462 schools in 18 states, about two percent of the nation's schools. It will be added in schools in Mississippi, Tennessee, Pennsylvania and Arkansas this year. Each participating school receives the extra support for three years at a cost of $500,000 per school. Some districts receive funding as a grant from the group, which gets support from foundations, corporations and the U.S. Department of Education. 

The program began five years ago and has improved the pass rates on the AP tests every year! Read more about the program and how its pass rates on math and science AP exams stack up against national averages in Schoof's full report on McClatchy.

Monday, August 26, 2013

What the Wind Can Do as an Energy Source

The Gooru Corner featured wind as an energy source earlier in this month and as fall approaches and there's more breezes passing through, we couldn't think of a better time to highlight all the things wind can do.

The wind has many practical uses: flying a kite, going sailing, paragliding or just cooling off on a warm day. But did you know that wind can be harnessed as a renewable energy source as well? Check out this multimedia collection brought to you by Gooru Corner to learn about the benefits and consequences of wind power.

What would you do with wind power?  

Wednesday, August 21, 2013

Back to School: Be STEM Ready

You want to be STEM ready this year but getting together all of the resources - like, say a brand new multi-million dollar facility, STEM-prepared training for your staff and a plethora of STEM materials to name a few - can be tricky to say the least. But there's good news: your school is not alone. Go ahead and categorize yourself with all of the other schools doing everything they can to just get this STEM thing off the ground.

Nevertheless, Anne Jolly shows you how you can ramp up for some great STEM learning by following advice gathered from educators who have been teaching STEM classes successfully for several years. Let's get started!

As Jolly explains, prepare yourself for a noisy classroom where multiple right answers abound and failure is regarded as a positive step toward discovery and successful solution. You'll need to get ready for your kiddos to work closely together, using hands-on methods to solve real-world problems. This also means being willing to take a step back and give your students enough room to kick off their journey toward becoming creative, innovative, critical thinkers. 

Take a look at this checklist of five questions that your school needs to consider to get ready for their STEM adventure.
  1. Does everyone know why the school is implementing STEM and what STEM is designed to accomplish?
  2. What type of STEM program will your school implement initially and what do you want this program to become?
  3. How will you prepare and support teachers? What do teachers know/need to know, and how will they learn it?
  4. What will your school do about STEM curriculum?
  5. What resources are available?
Jolly cites answers to all five questions in her article on KQED's blog, Mind Shift. She even offers up multiple reasons or answers per question to make it easy for you to find one that applies to your school's situation. Check them out here.

In short: your school can be STEM-ready as long as you have a starting point and a long term goal. Jolly reminds us that the STEM initiative will keep growing with some visionary leadership. That being said, a knowledgeable and supportive school principal is the most important driver behind a STEM initiative. 

Another great Jolly suggestion: get a group of extra supportive parents to form a STEM booster club. 

Monday, August 12, 2013

Summer Science Experiment: Making Magic with Milk

The summer is winding down, but there's still time to squeeze in just a few more experiments before your kids head back to school. As usual, this experiment involves a small list of household products, but the end result reflects exploration and discovery. In this popular Dr. Mad Science experiment, you and your young scientists will observe how milk reacts with food coloring and soap.

Here's what you'll need:
  • Milk (it is recommended that you use 2%)
  • A bowl
  • Food coloring
  • Q-tips
  • Dish Soap (it is recommended that you use Dawn)
Now let's get started:
  1. Start by filling the bowl with milk and waiting for all the bubbles to go away.
  2. Put a large amount of food coloring in the center of the milk.
  3. Take Q-tips and dip them into the dish soap. Then put them in the middle of the bowl for 15 seconds.
  4. Watch as the food coloring expands on the surface of the milk.
So what about the science? Well here it is: milk contains protein and really small amounts of fat in it. Both proteins and fat are sensitive to chemical changes. The chemicals in the dish soap weaken the chemical bonds that hold the protein together in the milk solution and the food coloring allows us to visually see the changes in the protein molecules. Likewise, the soap molecules cause the fat in the milk to mix and swirl until the fat has been distributed across the entire amount of the milk.

Watch Dr. Mad Science do it!

Friday, August 2, 2013

Summer Science Experiment: Backyard Bottle Rocket

Have you ever wondered what launches a rocket? Would you ever guess that it was something as simple as built up pressure? Well try it our for yourself and make a bottle rocket in your backyard this weekend!

Here's what you'll need:
  • An empty plastic bottle
  • Cardboard made into a cone and 4 fins
  • A cork
  • A pump with a needle adapter
  • Water
Now let's get started:
  1. Push the needle adapter of the pump through the cork and make sure it goes all the way through. To do this you may have to trim the cork down a little bit.
  2. Take your cardboard cone and fins and apply them to the bottle. (The cone at the top and the four fins at the bottom, so that the bottle resembles a rocket.)
  3. Fill the bottle with water until it's about a quarter full and then push the cork in tightly.
  4. Attach the pump to the needle adapter. If your bottle rocket won't stand up on it's own with the fins you made, rest it on a table, but if you make strong fins, you should fine and your bottle should stand up on its own.
  5. Pump air into the bottle and prepare for lift off! Make sure that everyone is standing away from the bottle as it will go up in the air with force after just a few seconds.

So what about the science? Check out Science Spark's explanation.

Friday, July 26, 2013

Summer Science Experiment: Make it Rain!

You may have more rain than you'd like this summer, but for those sweating out the summer and doing their best to make it through another drought, the four letter word never sounded so good.  Either way, why not make some rain of your own?! Help your kids understand the weather and what really causes it. This might even help curb some weather related fears your little ones are hanging on to. 

Grab these items to get started:
  • Glass Jar
  • Hot, hot water
  • Plate
  • Ice Cubes
Once you have you're supplies, get started! (And it's totally okay to call yourself the rain man/woman if you'd like.)
  1. Heat your water until it is just about boiling and pour it into your glass jar.
  2. As quickly as you can, cover the glass jar with your plate and then place the ice cubes on top. You might also want to keep a towel handy for any unexpected spills that might occur.
  3. Sit back and watch what happens as it begins to rain inside your jar! 
So what's really happening, here? The warm, moist air from the water rises and mixes with the cool air created by the ice cubes causing condensation first, and then rain. 

Friday, July 19, 2013

Summer Science Experiment: Ocean in a Jar!

Heat waves are affecting everyone this summer and nothing sounds better than hitting the beach to relax and cool off. If you can't go to the beach, make this ocean in a jar with your kids this weekend - complete with lessons about density and waves. The catch? They'll be having so much fun they won't even realize they're learning at the same time.

The lesson: water is denser than oil and the two liquids never mix. So, when the water in your ocen jar moves, it pushes the oil around making shapes like waves.

Here's what you'll need:
  • Clear jar or bottle with lid
  • Water
  • Blue food coloring
  • Glitter
  • Baby Oil
  • Plastic floating toys
Now get started on bring the ocean to you:
  1. Fill the jar or bottle halfway with water.
  2. Add drops of the blue food coloring until your like the color you see. Shake in a little glitter to add a little pizazz to your ocean water.
  3. Pour baby oil into the jar until it's three-quarters full.
  4. Place a floating toy or multiple floating toys on top of the oil, and then screw the lid on until it's pretty snug and tight.
  5. Shake the jar gently to make some waves and set your ocean in motion! Think about this: when you shake the jar side to side are the waves produced different than those you see when you shake the jar in an up-and-down motion? 

Tuesday, July 16, 2013

Chocolate Chip Cookies: Science-fied!

The following recipe for chocolate chip cookies was adapted from a recipe that appeared in Chemical & Engineering News (C&EN, June 19, 1995, p. 100). It was attributed to Jeannene Ackerman of Wico Corp. The recipe was published in Fisher Science Education's March/April 2013 issue of Headline Discoveries.

Ever wonder what a chocolate chip cookie looks like from a chemist's perspective? 

The ingredient list will probably look a lot like this:
  • 532.35mL (283 grams) finely milled wheat grains
  • 4.9mL NaHCO3
  • 4.9mL refined halite
  • 226.8 grams (2 rectangular prisms) partially hydrogenated tallow triglyceride
  • 177.45mL crystalline sucrose (C12H22O11)
  • 177.45mL sucrose-molasses mixture
  • 4.9mL vanillin-ethanol solution
  • Two calcium carbonate-encapsulated avian albumen-coated protein
  • 473.2mL theobroma cacao
And here's how a chemist would go about making these ooey-gooey favorites:
  1. Add the finely milled wheat grains, NaHCO3 and refined halite to a 2L jacketed round reactor vessel (reactor #1) equipped with a sir mechanism.
  2. In a second 2L reactor vessel fitted with a radial flow impeller operating at 100 rpm, app the triglyceride, sucrose, score-molasses mixture and vanillin-ethanol solution until the mixture is homogenous.
  3. Add the encapsulated albumen-coated protein followed by three equal portions of the homogenous mixture in reactor #1. Add the theobroma cacao slowly with constant agitation. Care must be taken at this point in the reaction to control any temperature rise that may be the result of an exothermic reaction.
  4. Divide the resulting slurry into spheres each approximately 65mL in volume. Place individual spheres on a 316 SS sheet (300 x 600mm). Heat in a 450°K oven for a period of time that is in agreement with Frank & Johnston’s first order rate expression (see JACOS, 21, 55), or until golden brown.
  5. Once the reaction is complete, place the sheet on a 300°K heat-transfer surface allowing the product to come to thermal equilibrium.
Want to take this recipe (or yummy experiment, whatever you'd like to call it) to the next level? Think about these discussion points: 
  • If you wanted to add peanuts or dark chocolate to your cookies, what would you add to the list of ingredients?
  • Write your own chemist's recipe for a baked treat using the format above.