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A hydrogen powered vehicle

10/27/2017

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The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.
 
There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report.  This way the teacher has the option!  Each lab is two pages to allow for one two-sided handout. 
 
A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you. 
I teach high school chemistry and this is exactly what i was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”
 
 You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now.  It’s a great resource!
 
http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html
 
*Some of you have already purchased my lab book – be sure to check out Page 141 !

*This Blog contains several entries that would be helpful to your chemistry classroom.  Check out the Topic List to help you to find past Blog entries.
 
Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.
 
“Fuel cell vehicles use hydrogen gas to power an electric motor. Unlike conventional vehicles which run on gasoline or diesel, fuel cell cars and trucks combine hydrogen and oxygen to produce electricity, which runs a motor. Since they’re powered entirely by electricity, fuel cell vehicles are considered electric vehicles (‘EVs’)—but unlike other EVs, their range and refueling processes are comparable to conventional cars and trucks.
Converting hydrogen gas into electricity produces only water and heat as a byproduct, meaning fuel cell vehicles don’t create tailpipe pollution when they’re driven. Producing the hydrogen itself can lead to pollution, including greenhouse gas emissions, but even when the fuel comes from one of the dirtiest sources of hydrogen, natural gas, today’s early fuel cell cars and trucks can cut emissions by over 30 percent when compared with their gasoline-powered counterparts. Future renewable fuel standards—such as the requirements currently in place in California—could make hydrogen even cleaner.
Because fuel cell vehicles are only beginning to enter the U.S. market, interested drivers should ensure they live near hydrogen refueling stations.”
http://www.ucsusa.org/clean-vehicles/electric-vehicles/how-do-hydrogen-fuel-cells-work#.We4ELzBrzcs
 
“Hydrogen fuel is a zero-emission fuel when burned with oxygen, if one considers water not to be an emission. It often uses electrochemical cells, or combustion in internal engines, to power vehicles and electric devices. It is also used in the propulsion of spacecraft and might potentially be mass-produced and commercialized for passenger vehicles and aircraft.
Hydrogen lies in the first group and first period in the periodic table, i.e. it is the first element on the periodic table, making it the lightest element. Since hydrogen gas is so light, it rises in the atmosphere and is therefore rarely found in its pure form, H2. In a flame of pure hydrogen gas, burning in air, the hydrogen (H2) reacts with oxygen (O2) to form water (H2O) and releases energy [which is an exothermic reaction].

2H2(g) + O2(g) → 2H2O(g) + energy

If carried out in atmospheric air instead of pure oxygen, as is usually the case, hydrogen combustion may yield small amounts of nitrogen oxides, along with the water vapor.
The energy released enables hydrogen to act as a fuel. In an electrochemical cell, that energy can be used with relatively high efficiency. If it simply is used for heat, the usual thermodynamics limits on the thermal efficiency apply.

Since there is very little free hydrogen gas, hydrogen is in practice only an energy carrier, like electricity, not an energy resource. Hydrogen gas must be produced, and that production always requires more energy than can be retrieved from the gas as a fuel later on.[3] This is a limitation of the physical law of the conservation of energy. Most hydrogen production induces environmental impacts.“
https://en.wikipedia.org/wiki/Hydrogen_fuel
 
This author of an opinion article shares a concern about a hydrogen-powered vehicle, “Pictures of the Hindenburg and H-bombs flash through my mind. Would that be my fate in the event of a fender-bender? According to the Toyota Mirai’s website, if a high-speed collision were sensed by the vehicle, the flow of hydrogen would shut down. Which honestly makes me feel much safer, but does little to quell my imagination.”
https://www.cartalk.com/blogs/jc-howard/hy-life-behind-wheel-hydrogen-vehicle
 
“A hydrogen fuel cell is a simple machine. The core of the tech is a proton exchange membrane. On one side of the membrane you have pure hydrogen, and on the other side you have ordinary air. Ordinary air is about 80-percent nitrogen and 20-percent oxygen, plus trace amounts of other stuff. The proton exchange membrane is critical, because hydrogen and oxygen atoms really like to be together. …The membrane will allow hydrogen atoms to pass through to the oxygen, but only if the hydrogen atom gives up its electron on the way. We cleverly put some highly conductive metal like platinum on the walls of the fuel cell, so the electrons go there and run all the way around the fuel cell to get back to their hydrogen atoms; that action creates electrical current that we can use. When the oxygen and hydrogen are all coupled up and complete again, we’ve got a water molecule and some electricity for our trouble.” https://www.digitaltrends.com/cars/does-hydrogen-make-sense-as-an-automotive-fuel/
“There are a lot of ways to get hydrogen, and some are wackier than others. In the 19th century, people used to drop iron filings into barrels of sulfuric acid. The reaction produced hydrogen gas, which they ducted into balloons to go up in the air. … You can also use electricity to break apart water molecules using electrolysis, and you get pure hydrogen and oxygen. That’s great, but the laws of thermodynamics dictate that you’ll never get as much electricity back out of the hydrogen as you put into the system to break up the water molecules. …The third way to get hydrogen is equally problematic. You can reform natural gas, cracking the hydrocarbon molecules to break the hydrogen loose. But that means you’re still dependent on fossil fuel, and when you break out the hydrogen for your green power, you also produce carbon dioxide, which is a greenhouse gas. …Before we close on hydrogen generation, research is being done on photosynthesis of the element [hydrogen] using algae. It remains to be seen if that will work on a large scale, but it’s better than some of the other methods that have been tried.”
 
“On top of their high price tag, hydrogen fuel-cell vehicles have other disadvantages. Namely…a hydrogen fueling network is virtually nonexistent in the U.S. and would be expensive to build. Also, most hydrogen fuel is produced by burning natural gas to create hydrogen, a process called steam methane reformation. Natural gas is cleaner than gasoline, but the process does undercut the environmental benefits.  There’s also the challenge of low gasoline prices.”
https://epic.uchicago.edu/news-events/news/will-hydrogen-fuel-cell-cars-be-america%E2%80%99s-car-future
 
“Listed below are alternative fuels that are already being tested and used for vehicles worldwide:
  • Biodiesel Vehicles - PROs: Renewable and somewhat available, it can run in older diesel engines. CONs: Cost more than diesel plus there are supply issues.
  • Plug-In Hybrid Vehicles - PROs: Runs on electric for short commutes with gas engine for longer hauls. CONs: Big expensive batteries and the vehicle still uses gas.
  • Electric Battery Vehicles - PROs: Good torque, no harmful emissions and low operating cost per mile. CONs: Lacks convenience with limited range and long charging times.
  • CNG Vehicles - PROs: Compressed Natural Gas burns cleaner and cost less than gasoline. CONs: Limited range, huge tanks, non-renewable source and few refueling stations.
  • Hydrogen Fuel Cell Vehicles - PROs: Emission is water vapor, renewable energy source and great mileage. CONs: Few places to refuel, expensive and requires high-pressure for storage.
  • Ethanol Powered Vehicles - PROs: Can potentially be produced from garbage and waste with less harmful emissions. CONs: Currently made from natural gas and a very limited infrastructure for refueling.

According to the government's energy.gov. website, producing vehicles that use alternative fuels will help reduce the consumer's fuel costs, increase the nation's energy security and minimize global pollution.”
https://e3sparkplugs.com/blog/pros-and-cons-for-alternative-fuel-vehicles/
 
If you are talking/demonstrating/completing a lab generating hydrogen gas, this might be a handy topic to show a “real world” application.
 
A past blog post from 07/02/2015 titled “Hydrogen Production” may be a useful reference.
 
Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

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toxic water in puerto rico

10/20/2017

0 Comments

 
The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.
 
There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report.  This way the teacher has the option!  Each lab is two pages to allow for one two-sided handout. 
 
A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you. 
I teach high school chemistry and this is exactly what i was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”
 
 You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now.  It’s a great resource!
 
http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html
 
*Some of you have already purchased my lab book – be sure to check out Page 141 !

*This Blog contains several entries that would be helpful to your chemistry classroom.  Check out the Topic List to help you to find past Blog entries.
 
Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.
 
Mole Day is this Monday, October 23rd!  Check out past Mole Day posts:
 
01/10/2014           2nd Entry (Mole Conversions and
                                   Moletown Map)
10/20/2014           Celebrating Mole Day
10/15/2015           Mole Mathematics​
10/15/2016           Mole Day is Coming!
 
 “Friday afternoon [10/13/2017], CNN watched workers from the Puerto Rican water utility, Autoridad de Acueductos y Alcantarillados, or AAA, distribute water from a well at the Dorado Groundwater Contamination Site, which was listed in 2016 as part of the federal Superfund program for hazardous waste cleanup.
Residents…filled small bottles from a hose and piled them in their vehicles. Large trucks with cylindrical tanks on their backs carried the water to people elsewhere. Some of the trucks carried the name of the municipality of Dorado. Others simply were labeled with the words ‘Agua Potable,’ Spanish for potable water.”
http://www.cnn.com/2017/10/13/us/puerto-rico-superfund-water/index.html
 
“The U.S. environmental regulator warned residents of Puerto Rico on Wednesday [10/11/2017] not to break into wells at industrial waste sites as parts of the island still struggle with drinking water shortages three weeks after Hurricane Maria hit.
‘There are reports of residents obtaining, or trying to obtain, drinking water from wells at hazardous waste Superfund sites in Puerto Rico,’ the Environmental Protection Agency (EPA) said in a release.”
https://www.reuters.com/article/us-usa-puertorico-water/u-s-warns-puerto-rico-against-tapping-water-at-toxic-waste-sites-idUSKBN1CH0B9
 
“Superfund sites are areas contaminated by hazardous industrial waste that have been identified by the EPA as candidates for a federal clean-up program.
The EPA advised against ‘tampering with sealed and locked wells or drinking from these wells, as it may be dangerous to people's health.’ …
Toxic waste is not the only drinking water worry in Puerto Rico. The agency said raw sewage continues to be released into waterways and is expected to continue until repairs can be made and power is restored. The EPA advised people to boil water from rivers and streams for one minute, or disinfect it with bleach.”
http://time.com/4979095/puerto-rico-drinking-water-waste-sites/
 
This post contains a 3-minute news report about this situation:
http://www.hawaiinewsnow.com/story/36605719/puerto-rico-residents-risk-health-drinking-contaminated-water
From this video, “If I don’t drink water, I’m gonna die.  I might as well drink this water.”
 
From a Sunday, 10/15/17 news report, “ Rep. Bennie Thompson, the ranking Democrat on the House Homeland Security Committee, wrote a letter to acting Homeland Security Secretary Elaine Duke asking for the investigation. Thompson, from Mississippi, said he wanted to know whether she was aware Americans there are drinking water from possibly contaminated sources.
‘Reports of Puerto Ricans waiting hours to receive potentially contaminated water that could have long-term health consequences is beyond disturbing,’ Thompson said Saturday. ‘That it happened on days after EPA warned the people of Puerto Rico to refrain from breaking into Superfund sites to access water suggests a troubling breakdown in coordination among the federal entities playing a role in federal disaster response activities. ‘
The EPA had told CNN it was planning to do testing on wells around the Dorado site this weekend.”
http://wtvr.com/2017/10/15/puerto-ricans-using-water-from-dorado-groundwater-contamination-hazardous-waste-site/
 
Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

0 Comments

overview of global climate change

10/13/2017

0 Comments

 
The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.
 
There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report.  This way the teacher has the option!  Each lab is two pages to allow for one two-sided handout. 
 
A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you. 
I teach high school chemistry and this is exactly what i was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”
 
You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now.  It’s a great resource!
 
http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html
 
*Some of you have already purchased my lab book – be sure to check out Page 141 !

*This Blog contains several entries that would be helpful to your chemistry classroom.  Check out the Topic List to help you to find past Blog entries.
 
Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.
 
At this time of year schools are mailing home Progress Reports of student classroom performance.  Some past blog posts that may be helpful include:
 
07/20/2014             Classroom Grading Programs
09/30/2015             5-Week Progress Reports

Oh, and Mole Day is coming, Monday, October 23rd!  Check out past Mole Day posts:
 
01/10/2014           2nd Entry (Mole Conversions and
                                   Moletown Map)
10/20/2014           Celebrating Mole Day
10/15/2015           Mole Mathematics​
10/15/2016           Mole Day is Coming!
 
 “Scientists know that certain gases trap heat and act like a blanket to warm the planet. One of the most important is carbon dioxide (CO2), which we release into the atmosphere when we burn fossil fuels — oil, coal, and natural gas — to generate electricity, power our vehicles, and heat our homes.
As we overload our atmosphere with carbon dioxide, more and more heat is trapped — and Earth steadily warms up in response. How do we know? The scientific evidence is overwhelming.”
http://www.ucsusa.org/our-work/global-warming/science-and-impacts/global-warming-science#.WdZNxNFrzcs
 
“Timeline (Milestones)
Here are gathered in chronological sequence the most important events in the history of climate change science.”
https://history.aip.org/climate/timeline.htm
 
This brief animation (35 seconds) shows the increase in global temperatures from the years 1900 through 2016, and it’s very easy to see:
http://www.climatecentral.org/news/history-global-warming-animation-21670
 
View the graph at the top of the page showing the dramatic increase in carbon dioxide level from 1950 to the 2000s:
https://climate.nasa.gov/evidence/
 
“The current warming trend is of particular significance because most of it is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and proceeding at a rate that is unprecedented over decades to millennia.
Earth-orbiting satellites and other technological advances have enabled scientists to see the big picture, collecting many different types of information about our planet and its climate on a global scale. This body of data, collected over many years, reveals the signals of a changing climate.
The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century. Their ability to affect the transfer of infrared energy through the atmosphere is the scientific basis of many instruments flown by NASA. There is no question that increased levels of greenhouse gases must cause the Earth to warm in response.
Ice cores drawn from Greenland, Antarctica, and tropical mountain glaciers show that the Earth’s climate responds to changes in greenhouse gas levels. Ancient evidence can also be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks. This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly ten times faster than the average rate of ice-age-recovery warming.”
http://ossfoundation.us/projects/environment/global-warming/climate-science-history
This page also provides timelines and short video segments about the history and prediction of Global Warming.
 
Here is one more timeline about the topic of Climate Change/Global Warming:
http://www.bbc.com/news/science-environment-15874560
 
“When was human-driven climate change discovered and when did the world of politics/policy first take notice?
We could begin in the 1820s when Joseph Fourier first suggested that gases in the atmosphere trap some of the sun's heat like glass in a greenhouse (hence the ‘greenhouse effect’). We could also begin in the 1860s with John Tyndall measuring the capacity of water vapor and CO2 to trap infrared light (the ground under your feet emits long wavelength infrared radiation after it is warmed by the incoming sunlight which arrives mostly at shorter wavelengths). It was Tyndall who came up with the potent metaphor of greenhouse gases as a ‘blanket’ covering the Earth. …
The first calculation of the greenhouse effect to include human-driven release of greenhouse gases came about 100 years ago. Using estimates of coal burning, Swedish chemist Svante Arrhenius built on other calculations he'd made and estimated that doubling the CO2 content of the planet's atmosphere would raise its temperature by 2.5 to 4.0 degrees Celsius.
That is where it all begins.
But surely Arrhenius' calculation was too simple. Think of all the details he missed. What about the influence of the vast oceans that are constantly soaking up CO2? That must make a huge difference. It might, but that question was answered more than 60 years ago.
It was in 1957 that Roger Revelle at the Scripps Institution of Oceanography and Hans Suess of the U.S. Geological Survey discovered the chemical pathways of ocean CO2 uptake. Their findings showed the oceans to be limited in their ability to absorb the CO2 we released through burning fossil fuels. While their calculations have been refined over time, their basic conclusions have stood the test of time.
From Arrhrenius to Revelle to right now. That's 100 years of climate science reaching the same conclusion. “
http://www.npr.org/sections/13.7/2014/05/13/312128173/the-forgotten-history-of-climate-change-science
 
“Like a prehistoric fly trapped in amber during dinosaurs' days, airborne relics of Earth's earlier climate—including dust, air bubbles, sea salts, volcanic ash, and soot from forest fires—can end up trapped in glacial ice for eons. To climate scientists, those relics tell a story about how our planet's climate and atmosphere have changed over thousands of years. …
After analyzing enough ice core slices, which may each represent anywhere from a week to a year of time, a researcher can look for patterns to track changes in the atmosphere's composition and temperature, and what activity on Earth shaped it.
The ratio of ‘light’ oxygen-16 to ‘heavy’ oxygen-18 in a sample, for instance, reveals the global temperature when the ice formed; it takes colder temperatures for water vapor containing the lighter oxygen isotope to turn into precipitation. Examining the gasses trapped in ice cores is how scientists first learned that the amount of carbon dioxide and the global temperature have been linked at least the last million years of Earth's history. …
Scientists hope to collect a new ice core from the eastern side of the Trans-Antarctic Mountains, which today separate the East and West Antarctic Ice Sheets. Much of the land under the West Antarctic Ice Sheet is below sea level. If the ice sheet did disintegrate, then the proposed ice core drilling location—presently in the middle of the frozen continent—would have been coastal real estate 125,000 years ago.”
https://www.climate.gov/news-features/climate-tech/climate-core-how-scientists-study-ice-cores-reveal-earth%E2%80%99s-climate
 
According to the Union of Concerned Scientists:
“Global warming is already having significant and harmful effects on our communities, our health, and our climate. Sea level rise is accelerating. The number of large wildfires is growing. Dangerous heat waves are becoming more common. Extreme storm events are increasing in many areas. More severe droughts are occurring in others. 
We must take immediate action to address global warming or these consequences will continue to intensify, grow ever more costly, and increasingly affect the entire planet—including you, your community, and your family.
The good news is that we have the practical solutions at hand to dramatically reduce our carbon emissions, slow the pace of global warming, and pass on a healthier, safer world to future generations.”
http://www.ucsusa.org/global_warming#.WdZOqtFrzcs
 
“The outcome of any significant climate change will be varied rather than simply an overall increase in average or nocturnal temperatures. Climate researchers have designed models to predict the longer-term consequences both in air and ocean circulation patterns. These reproduce observed continental-scale surface temperature patterns and trends over many decades, including the more rapid warming since the mid-20th century and the cooling immediately following large volcanic eruptions, thus giving a range and probability of climatic impacts on different regions of the world. The models are constantly being refined, and in 2013 the [Intergovernmental Panel on Climate Change or the] IPCC noted ‘differences between simulated and observed trends over periods as short as 10 to 15 years (e.g. 1998 to 2012)’, ie shorter term than the models. Climate is defined as the statistical average of weather over a long period, typically 30 years.”
http://www.world-nuclear.org/information-library/energy-and-the-environment/climate-change-the-science.aspx
 
Future blog posts may refer to Climate Change; also, your students may hear more about it in the news.  This could be a topic for Extra Credit research.
 
Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

0 Comments

Feeding Seaweed to Cows

10/6/2017

3 Comments

 
The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.
 
There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report.  This way the teacher has the option!  Each lab is two pages to allow for one two-sided handout. 
 
A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you. 
I teach high school chemistry and this is exactly what i was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”
 
 
You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now.  It’s a great resource!
 
http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html
 
*Some of you have already purchased my lab book – be sure to check out Page 141 !
 
 “A [Prince Edward Island] dairy farmer's attempt to save money on feed — he fed his cows seaweed from a nearby beach — has led to a discovery that could bring a substantial reduction in greenhouse gases worldwide.
A researcher found the seaweed reduced the methane in the cows' burps and farts, a key contributor to climate change.
‘Considering that agriculture is one of the big contributors to the global greenhouse gas inventory, it's pretty huge,’ said agricultural scientist Rob Kinley.
More than 10 years ago, Joe Dorgan was a dairy farmer in Seacow Pond, near the northwestern tip of the province, with many of his cows grazing near the shore.
He decided to convert to an organic dairy farm and, as a way to save money, he started feeding seaweed to the cows as their source of minerals and vitamins. … The seaweed is plentiful and washes up on the local beaches where it is gathered using rakes hauled by horses.
‘This is 100 per cent natural. As the storms toss it ashore on the beach, we gather it, dry it, process it and feed it,’ he said.”
http://www.huffingtonpost.ca/2016/12/02/seaweed-cows-greenhouse-gases_n_13373556.html
 
According to a 2016 report, “A team of Australian scientists lead by Rocky De Nys (James Cook University) discovered that a certain type of red seaweed, called Asparagopsis taxiformis, can decrease the amount of methane produced by the bacteria found in a cow’s stomach.
Lauren Kuntz explains that methane is a very potent but short-lived greenhouse gas. Limiting methane produced by livestock, a major source of the gas, could help abrogate short-term dramatic global warming (on the scale of a few decades). It would not, however, eliminate the need to cut down on carbon dioxide emissions. Carbon dioxide contributes to the global warming via the greenhouse effect and remains in the atmosphere for a much longer time than methane.”
http://sitn.hms.harvard.edu/flash/2016/seaweed-may-cut-cows-methane-production/
 
“While previous studies have focused on the role of methane in greenhouse trapping of the infrared energy emitted by the Earth and its atmosphere, this new study also took into account the way methane absorbs energy from the sun, at shorter wavelengths. It shows that much of the extra absorption is in the lower part of the atmosphere, where it has a warming effect.“
https://phys.org/news/2017-01-effect-methane-climate-greater-thought.html
 
“Cows and other cud-chewing animals digest their cellulose-laden food with the help of stomach bacteria in a process called enteric fermentation, which is why they can live happily on grass. The end result of such microbial metabolism is methane, of which the average cow produces some 200 to 500 liters per day.
Actually, despite a lot of jokes about farting cows, the bulk of methane emissions— about 90 percent—come from their slightly less impolite burps. According to the United Nations Food and Agriculture Organization (FAO), global livestock collectively burp and poot about seven gigatonnes (that’s seven billion metric tons) of CO2-equivalents each year. About 14.5 percent of anthropogenic greenhouse gas emissions come from livestock. That is more than global car and airplane traffic emissions combined.”
http://www.nationalgeographic.com/people-and-culture/food/the-plate/2016/11/seaweed-may-be-the-solution-for-burping-cows/
 
“Scientists at the Cow Research Institute in Mathura, around 100 miles south of New Delhi, are tinkering with cattle feed, seeking a formula that will create less gas for the cows to belch out. (That is how most of it is released, by the way; scientists say much less comes from farting.)
But a team of researchers in the southern state of Kerala is working on a long-term answer.
E.M. Muhammed, a breeding expert, has been experimenting with an indigenous strain of miniature cattle that produce less milk than typical crossbred cows but are much better able to stand very hot weather. An unexpected surprise along the way, he said, was that these dwarf animals, which are about one-quarter the weight of crossbred cows, produce only one-seventh as much manure and one-tenth as much methane.”
https://www.nytimes.com/2016/05/04/world/what-in-the-world/india-cows-carbon-emissions.html?mcubz=0
 
“A recent [June 2017] study by researchers at James Cook University in Queensland, Australia, has found a certain type of Australian red algae can significantly inhibit methane emissions from cows. Led by Professor of Aquaculture Rocky De Nys, researchers found an addition of less than 2 percent dried seaweed to a cow’s diet can reduce methane emissions by 99 percent. The study was conducted in collaboration with the Commonwealth Scientific and Industrial Research Organization (CSIRO), an Australian federal research agency.
Methane is about 25-times more potent than carbon dioxide in a 100-year time span, and a single cow releases between 70 and 120 kilograms of methane per year. Burps from cows account for 26 percent of the United States’ total methane emissions, and the U.S. is only the world’s fourth-largest producer of cattle, behind China, Brazil, and India. There are currently approximately 1.3 to 1.5 billion cows roaming the planet.
Researchers started investigating the potential effect of seaweed on cows in 2005, when a dairy farmer named Joe Dorgan inadvertently conducted an experiment on his herd in Prince Edward Island, Canada. Dorgan noticed cows that grazed on washed-up seaweed in paddocks along the shore were healthier and more productive than those that stayed in the field. He began feeding his cows a mixture of local storm-tossed seaweed and found the new diet saved him money and induced ‘rip-roaring heats,’ or longer cycles of reproductive activity.
Dorgan is not the first farmer to discover the beneficial properties of seaweed in farm animals. The practice was used by Ancient Greeks in 100 B.C, according to the U.N. Food and Agriculture Organization. There are also records of Icelandic farmers using kelp and algae to keep livestock healthy and produce larger milk yields.”
https://foodtank.com/news/2017/06/seaweed-reduce-cow-methane-emission/
 
This topic can be a useful Homework or Extra Credit topic when discussing the naming of compounds such as methane, CH4, and carbon dioxide, CO2.

*This Blog contains several entries that would be helpful to your chemistry classroom.  Check out the Topic List to help you to find past Blog entries.
 
Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.
 
Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

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    Marjorie R. Heesemann is a chemistry teacher with 15 years of experience who is now working to develop resources for the Chemistry classroom.

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