Teaching High School Chemistry
  • Introduction
  • Book
  • Blog
  • Topic List
  • Teaching Resources
  • Biography
  • Contact

Definition of the kilogram just changed

5/31/2019

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 !
 
 “…130 years after it was established, the kilogram as we know it is about to be retired. But it's not the end: …20 May 2019, a new definition will be put in place - one that's far more accurate than anything we've had until now.”
https://www.sciencealert.com/tomorrow-the-definition-of-the-kilogram-will-change-forever-here-s-what-that-really-means

“For example, a metre is determined by the distance light travels in a vacuum in 1/299792458 of a second. A second is determined by the time it takes for a caesium atom to oscillate 9,192,631,770 times.

A kilogram is defined by… a kilogram.

No, literally. It's a kilogram weight called the International Prototype of the Kilogram (IPK), made in 1889 from 90 percent platinum and 10 percent iridium, and kept in a special vault in the BIPM headquarters.

In fact, the kilogram is the only base unit in the SI still defined by a physical object.”

“The new definition of the kilogram, which was adopted at an international conference [in] … Versailles, France, went into effect Monday [05/20-19]. Instead of being based upon a shiny hunk of metal stored in a vault in Sevres, France, on the outskirts of Paris, the kilogram is now based on the Planck constant, a tiny, unvarying number that plays a key role in quantum physics. ...

The kilogram was redefined in order to create a precise, unchanging standard for its value, according to Henson. More than a century of cleanings and exposure to air had caused the original French prototype — known as the International Prototype of the Kilogram, or ‘Le Grand K’ — to lose about 50 micrograms. That’s roughly the mass contained within a handful of fingerprints. …

Since it’s based not on a physical object but on a mathematical constant, the new kilogram isn’t subject to such changes. And while 50 micrograms doesn’t sound like much, Jon Pratt, an engineer at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, said the more accurate definition would make a big difference for researchers working with tiny quantities of medications, radioactive compounds and other materials requiring nanoscale precision.

What will the new kilogram mean for the rest of us? Experts say not much. ‘You don’t need to panic,’ Henson said, adding that the switch had been designed to go unnoticed by most people. ‘Nothing is going to change.’

In other words, a kilogram of something at the store or on the scale will continue to be equivalent to about 2.2 pounds."
https://www.nbcnews.com/mach/science/definition-kilogram-just-changed-here-s-what-means-ncna1007731
 
 “Although the value of the kilogram will not change, the redefinition of the kilogram using a constant will ensure it remains reliable, and enable far more accurate mass measurements in the future.

The Planck constant describes the behavior of particles and waves on the atomic scale and depends on three units: the meter, kilogram and second. As the second and meter are measured and defined by the speed of light, they can be used with the fixed Planck constant to define a kilogram.
 
The Planck constant is, in turn, measured using an instrument known as the Kibble balance, first developed at NPL by the late physicist Bryan Kibble.

‘The redefinition of the kilogram is a tremendous leap for the international measurement community and science as a whole,’ said NPL fellow Ian Robinson, who worked on the device's development with Kibble... .

‘By using a universal constant of nature to define the kilogram we have enabled the whole world to contribute to the topmost level of mass measurement and, in addition, paved the way for future innovations. Much like upgrading a building's foundations, we're building a stable base for future science and industry.’ "
 
https://www.cnn.com/2019/05/20/world/new-kilogram-introduced-scli-intl-scn/index.html
 
You may want to use an article from those posted in this Blog have students write an Essay question for your Final Exam.

Past blog posts about Final Exams and the End of the School Year include:

06/08/2014            Final Exams – End of Year Preparation
06/15/2014            End of Year Activity – Lab Clean-Up
06/29/2014            Summer Vacation
05/28/2015             Extra Credit II
06/11/2015             End of Year Reflection
06/04/2015             Final Exams II
06/19/2016             End of Year Reflection II

*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!

0 Comments

earliest molecule in the universe

5/24/2019

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 !
 
 “When the universe formed during the Big Bang 13.8 billion years ago, the chemical reactions of the aftermath formed the first molecules. Those first molecules were crucial in helping form everything we know, but they're also absent.

And although HeH+, the helium hydride ion, has been proposed for years as that first molecule, scientists couldn't find any evidence of its existence in space -- until now. The findings were published Wednesday [04/17/19]  in the journal Nature.

After the Big Bang, HeH+ formed in a molecular bond when helium atoms and protons combined. Later, these would break apart into hydrogen molecules and helium atoms. Both elements are the two most abundant throughout the universe, with hydrogen first and helium second. “
https://www.cnn.com/2019/04/17/world/earliest-molecule-in-the-universe-scn/index.html

“Researchers have detected the first molecule in space that was formed after the Big Bang. Previously, they had searched for helium hydride ions for decades. The finding could help to further understanding of the early development of the universe, reports a team led by Rolf Güsten from the Max Planck Institute for Radio Astronomy in Bonn in the journal ‘Nature’.

Helium hydride ions were the first molecules to form in the universe after the Big Bang about 13.8 billion years ago. Although the existence of the ion, a compound of ionised hydrogen and helium, was shown in the laboratory as early as 1925, it remained undetectable in space for a long time. ‘To date, there have simply been no appropriate detectors’, said astrophysicist Güsten."
http://www.general-anzeiger-bonn.de/ga-english/Researchers-from-Bonn-determine-the-oldest-molecule-in-space-article4090654.html
 
“The lack of evidence of the very existence of helium hydride in interstellar space was a dilemma for astronomy for decades,” says Rolf Guesten of the Max Planck Institute for Radio Astronomy, in Bonn, Germany, and lead author of the paper, in a press statement.

The dilemma was solved by NASA’s Stratospheric Observatory for Infrared Astronomy, or SOFIA. The world’s largest airborne observatory, SOFIA is an 80/20 partnership of NASA and the German Aerospace Center (DLR). It's an airplane—an extensively modified Boeing 747SP aircraft carrying a 2.7-meter (106 inch) reflecting telescope.

Helium hydride has long presented challenges to scientists. In the late 1970s, while studying a planetary nebula called NGC 702, a growing suspicion formed that it could be a cradle for this earliest of molecules. But nothing, not even space telescopes, could clear the noise of the nebula for the specific signal of helium hydride.

So scientists turned to SOFIA. The plane flies at 45,000 feet, above the interfering layers of the Earth's atmosphere. While it can't get as close to objects in space as the Hubble, it does have one serious advantage—it can come back to Earth. That means scientists can make adjustments based on why they are searching the skies. …

One of those instruments is known as the German Receiver at Terahertz Frequencies, or GREAT. Scientists were able to alter GREAT by adding a channel specifically geared towards helium hydride. Similar to a radio receiver, GREAT was able to tune into the frequencies generated by helium hydride molecules.”
https://www.popularmechanics.com/space/deep-space/a27194188/nasa-oldest-molecules-in-the-universe/
 
“The Big Bang itself produced just a handful of elements (variations of hydrogen, helium and lithium nuclei), so researchers have a pretty good sense of what the first atoms and molecules might have been. But the very first molecular bond to form, linking together atoms of different elements in a single molecule, has long been missing in action.

Known as a helium hydride ion (HeH+), this conglomeration of basic bits is just a helium atom and a hydrogen’s nucleus (aka a proton) stuck together. As the first compound created in the universe, you’d expect there to be traces of it throughout the universe — but astronomers couldn’t find it. (Scientists managed to produce some in the lab in 1925, so at least they knew it wasn’t an impossible substance.)”

http://www.astronomy.com/news/2019/04/astronomers-find-oldest-type-of-molecule-in-space
 
“SOFIA took three flights in May 2016, climbing as high as 45,000 feet, to observe the planetary nebula NGC 7027, Maria Temming reports for Science News. Positioned about 3,000 light-years away, the planetary nebula is an expanding cloud of gas surrounding a star that was once similar to the sun but has ejected most of its material, leaving behind a stellar remnant called a white dwarf. Within the hot gas of the nebula, SOFIA was able to pick out the signature of helium hydride in infrared light. …

Helium hydride is not a particularly stable molecule, but scientists were able to create the positively charged ion in the lab in 1925, reports Bill Andrews for Discover. Astronomers have hoped to find the molecule in a nebula for decades, and in the 1970s, observations of NGC 7027 suggested that it might have the right conditions—high heat and large amounts of ultraviolet radiation—for helium hydride to form.

More recently, an upgrade to one of SOFIA’s instruments, the German Receiver at Terahertz Frequencies (GREAT), allowed the airborne telescope to search for the wavelength of light emitted by helium hydride ions. The instrument works like a radio receiver, according to the NASA statement, and telescope operators can tune to the correct frequency to search for specific molecules.

The helium hydride observed by SOFIA was formed in NGC 7027, long after the first molecules were created more than 13 billion years ago. But the lead author of the new study, Rolf Güsten of the Max Planck Institute for Radio Astronomy in Germany, and his team plan to use the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to search for helium hydride that was created shortly after the big bang. If they are successful, humanity will have peered back in time billions of years and spotted some of the first building blocks of everything that was to come.”
https://www.smithsonianmag.com/smart-news/nasas-flying-telescope-spots-oldest-type-molecule-universe-180972000/
 
“Adam Perry, who studied helium hydride while at the University of Illinois Urbana-Champaign, likens the new find to unearthing a fossil that fills a missing link in animal evolution. “Everybody knew [helium hydride] had to be out there,” says Perry, who wasn’t involved in the study. But ‘where before there wasn't any hard evidence, now there is.
… People who do astrochemistry are going to be very excited about this.’

Studying the helium hydride ions in NGC 7027 may offer new insights into the chemical reactions that form these ions, says study coauthor Rolf Güsten, an astrophysicist at the Max Planck Institute for Radio Astronomy in Bonn, Germany.
Güsten and colleagues also hope to use the Atacama Large Millimeter/submillimeter Array in northern Chile to scour the distant, early universe for helium hydride ions born soon after the Big Bang.

'Helium hydride is a finicky molecule. Helium itself is a noble gas making it very unlikely to combine with any other kind of atom. But in 1925, scientists were able to create the molecule in a laboratory by coaxing the helium to share one of its electrons with a hydrogen ion.

Then, in the late 1970s, scientists studying the planetary nebula called NGC 7027 thought that this environment might be just right to form helium hydride. Ultraviolet radiation and heat from the aging star create conditions suitable for helium hydride to form. But their observations were inconclusive. Subsequent efforts hinted it could be there, but the mystery molecule continued to elude detection. The space telescopes used did not have the specific technology to pick out the signal of helium hydride from the medley of other molecules in the nebula.”
https://www.sciencenews.org/article/first-type-molecule-form-universe-has-been-seen-space
 
About 2/3 down the page is a 1 ½ minute video describing the existence of hydrogen-hydride:
https://www.nasa.gov/feature/the-universe-s-first-type-of-molecule-is-found-at-last
 
“HeH+ is the strongest known acid on Earth and was first synthesized in a lab in 1925. Because it is made from hydrogen and helium — the two most abundant elements in the universe and the first to emerge from the nuclear reactor of the Big Bang 13.8 billion years ago — scientists have long predicted that the molecule was the very first one to form when the cooling universe allowed protons, neutrons and electrons to exist side by side in atoms.

Scientists can't rewind the universe to hunt for this fledgling molecule where it was born, but they can look for it in parts of the modern universe that best replicate those superhot, superdense conditions — in the young nebulae of gas and plasma that explode out of dying stars.

These so-called planetary nebulae form when sun-like stars reach the end of their lives, blast away their outer shells and shrivel into white dwarfs to slowly cool into crystal balls. As those dying stars cool, they still radiate enough heat to strip nearby hydrogen atoms of their electrons, turning the atoms into the bare protons that are required for HeH+ to form.

Detecting HeH+ in even the closest planetary nebulae to Earth is tricky, because it glows at an infrared wavelength that is easily obscured by our own planet's atmosphere. In the new study, researchers got around that atmospheric haze by using a high-tech telescope mounted on a moving aircraft called SOFIA (the Stratospheric Observatory for Infrared Astronomy).”
https://www.livescience.com/65256-first-molecule-in-the-universe.html
 
You may want to use an article from those attached to write an Essay question for your Final Exam.
 
*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!


0 Comments

Britain goes one week without burning coal

5/17/2019

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 !
 
“For the first time in nearly 150 years, Britain has gone an entire week without burning any coal. The record follows the recent news that in April, renewable electricity surpassed coal-produced electricity in the United States for the first time as well.

The last time Britain went a week without coal was in 1882, when the first coal-fired plant opened in London. Since then, coal has been burned nearly every day to produce electricity for the country. But on May 1, every coal-fired generator was shut down. None of them were restarted until this past Wednesday, marking an entire week without coal.

Instead of coal, the nation relied primarily on renewable energy along with standbys like oil, natural gas, and nuclear. Typically, coal is used to supply whatever power can’t be generated through these means, and because renewables like solar and wind can fluctuate, coal plants are often conscripted to meet goals.

On the flip side, though, when the sun is shining brightly and the wind is strong, the country can often get by with little or no coal at all. For instance, a period in 2017 saw so much renewable electricity generated that the price of electricity went negative for several hours.

As Britain builds more renewable electricity generators, coal usage has been dwindling, and this past week saw a substantial, although temporary, increase in renewable energy. Renewable electricity usually ticks upward at the beginning of spring when longer daylight hours combine with increased snowmelt running through dams.

Britain has pledged to reach zero coal production by 2025, with a completely carbon-free power grid by 2050. It’s an ambitious goal, but judging by last week’s results, it appears to be well on its way to succeeding.

The U.S., meanwhile, is much more dependent on coal than Britain, so it will be a long time before our coal production reaches zero.”
https://www.popularmechanics.com/science/energy/a27425079/britain-week-without-coal/
 
“Coal-fired power stations still play a major part in the UK’s energy system as a backup during high demand, but the increasing use of renewable energy sources such as wind power means it is required less. High international coal prices have also made the fuel a less attractive source of energy.

The latest achievement — the first coal-free week since 1882, when the world’s first coal plant opened at Holborn in London — comes only two years after Britain’s first coal-free day since the Industrial Revolution.

Burning coal to generate electricity is thought to be incompatible with avoiding catastrophic climate change, and the UK government has committed to phasing out coal-fired power by 2025.”
https://e360.yale.edu/digest/britain-went-one-week-without-burning-coal-the-first-time-since-1882
 
“Burning coal to generate electricity is thought to be incompatible with avoiding catastrophic climate change, and the UK government has committed to phasing out coal-fired power by 2025.

Reductions in coal use in the UK have been responsible for halving electricity generation emissions since 2013, according to the Committee on Climate Change (CCC), whose report last week called for the UK to pursue a target of net-zero carbon emissions by 2050.”
https://www.theguardian.com/environment/2019/may/08/britain-passes-1-week-without-coal-power-for-first-time-since-1882
 
“The news came as the Environment Agency's chairwoman Emma Howard Boyd warned that entire coastal communities might need help to move "out of harm's way in the longer term," as global temperatures rise by an expected 4 degrees Celsius (7.2 degrees Fahrenheit) by 2100.

‘We can't win a war against water by building away climate change with infinitely high flood defenses,’ Boyd said in a statement, adding that £1 billion ($1.3 billion) a year needed to be invested in flood management to combat the emergency.

On May 2, the country's Committee on Climate Change (CCC) urged the government to cut its greenhouse gas emissions to net zero by 2050. Currently the UK has a target of curbing greenhouse gas emissions by 80% by 2050, compared to 1990 levels. Emissions fell by 42% in 2016.”
https://www.cnn.com/2019/05/09/health/uk-coal-electricity-renewables-health-scli-intl/index.html
 
"As more and more renewables come onto our energy system, coal-free runs like this are going to increasingly seem like the new normal," a spokesperson for the UK National Grid told Bloomberg.

"We believe that by 2025 we will be able to fully operate Great Britain's electricity system with zero carbon."

By not burning any coal since last Wednesday 1 May [2019], power plants have helped the UK pass an early milestone of reaching over 1,000 coal-free hours this year, making it look likely that the nation will beat last year's feat of going for 1,800 hours without burning the fossil fuel for electricity.

It's a remarkable accomplishment, since it was only one year earlier than that, in 2017, when the UK succeeded for the first time in reaching 24 hours without burning coal.

Now, the UK is on track to make a whole week or even longer, and it's all thanks to how the nation's significantly shifted where its electricity comes from in recent times.

A decade ago, coal's contribution to the UK grid was around 40 percent – the primary source of energy. These days, it's dropped to well under 10 percent, a massive decrease, with an 88 percent reduction occurring between 2012 and 2018.
https://www.sciencealert.com/the-uk-is-in-the-midst-of-a-record-breaking-run-without-burning-coal-right-now
 
A past blog post was on 12/14/18 about the “London Killer Smog in 1952” .

*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!


0 Comments

germany shuts down coal plants

5/10/2019

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 !
 
“Germany, one of the world’s biggest consumers of coal, will shut down all 84 of its coal-fired power plants over the next 19 years to meet its international commitments in the fight against climate change, a government commission said Saturday [1/26/2019].

The announcement marked a significant shift for Europe’s largest country — a nation that had long been a leader on cutting CO2 emissions before turning into a laggard in recent years and badly missing its reduction targets. Coal plants account for 40% of Germany’s electricity, itself a reduction from recent years when coal dominated power production.”
https://ktla.com/2019/01/27/germany-to-close-all-coal-fired-power-plants-to-rely-primarily-on-renewable-energy/

"Germany will spend tens of billions of dollars to end its use of coal power within two decades, if a plan agreed to early Saturday by representatives of the power industry, environmental movement, miners and local interest groups becomes official policy.

The deal, hammered out after more than 20 hours of intense, often fractious negotiating among a 28-member commission appointed last year by Chancellor Angela Merkel, would be one of the most significant energy transformations a nation has yet attempted in the face of climate change.

Thirty countries have already set out proposals to cut their carbon emissions by eliminating coal, the dirtiest and cheapest fossil fuel, including Britain, Canada and Sweden. But none of those plans are of the scale laid out in Germany, an industrial giant that currently relies on coal for almost a third of its energy needs."
https://www.nytimes.com/2019/01/26/world/europe/germany-quit-coal-2038.html

“Germany long saw itself as a global leader in fighting climate change but was forced to concede in recent years that it would by miss its target date of 2020 to reduce CO2 emissions by 40% from 1990. It is expected to be 32% below 1990 levels by next year.

Germany and nearly 200 nations around the world agreed to the landmark Paris climate accord in 2015 to work to keep global warming ‘well below’ 2 degrees Celsius and pursue efforts to limit the rise to 1.5 degrees. The planet has already warmed by about 1 degree Celsius since pre-industrial times as a result of the human-caused build-up of greenhouse gases. Scientists say the world is already experiencing the consequences in the form of rising sea levels, more intense hurricanes and wildfires.

Despite its stumbles in recent years that led critics to accuse Germany of hypocrisy, Kemfert said Saturday’s decision will make it likely that Germany can meet the target of a 55% reduction from 1990 CO2 levels by 2030 and an 80% reduction by 2050.

 ‘It’s good that Germany now has a clear road map for the phase-out of coal and we’re on the path to becoming carbon-free,’ said Martin Kaiser, executive director of Greenpeace Germany and a member of the commission. He was also pleased that the commission recommended that utilities scrap plans to clear the last 250 acres of the Hambach Forest west of Cologne for a lignite open-pit mine. …

Included in the recommendations was that the phase-out target be reviewed every three years. Also, the final deadline could be moved forward, if possible, by three years to 2035.

The initial targets are considerable, calling for a quarter of the country’s coal-burning plants with a capacity of 12.5 gigawatts to be shut down by 2022. That means about 24 plants will be shut within the first three years. By 2030, Germany should have about eight coal-burning plants remaining, producing 17 gigawatts of electricity, the commission said.”
https://www.latimes.com/world/europe/la-fg-germany-coal-power-20190126-story.html?fbclid=IwAR01a-ILAaio_Bsj2jqlLk7vbFDVYNyNfwh4L3-izp78fdTNiKR_E1nXfDU
 
“The announcement marked a significant shift for Europe’s largest country — a nation that had long been a leader on cutting CO2 emissions before turning into a laggard in recent years and badly missing its reduction targets. Coal plants account for 40% of Germany’s electricity, itself a reduction from recent years when coal dominated power production. …

The plan includes some $45 billion in spending to mitigate the pain in coal regions. The commission’s recommendations are expected to be adopted by Chancellor Angela Merkel’s government.

‘It’s a big moment for climate policy in Germany that could make the country a leader once again in fighting climate change,’ said Claudia Kemfert, professor for energy economics at the DIW Berlin, the German Institute for Economic Research. ‘It’s also an important signal for the world that Germany is again getting serious about climate change: a very big industrial nation that depends so much on coal is switching it off.’

The decision to quit coal follows an earlier bold energy policy move by the German government, which decided to shut down all of its nuclear power plants by 2022 in the wake of Japan’s Fukushima disaster in 2011. …

Twelve of the country’s 19 nuclear plants have been shuttered so far.

The plan to eliminate coal-burning plants as well as nuclear means that Germany will be counting on renewable energy to provide 65% to 80% of the country’s power by 2040. Last year, renewables overtook coal as the leading source and now account for 41% of the country’s electricity.

German CO2 emissions fell appreciably in the early 1990s, largely because of the implosion of Communist East Germany and its heavily polluting industry. Still, the country continued to rely on coal-fired plants for a significant share of its electricity.

Powerful utilities and labor unions helped keep coal-burning plants operating and previous governments even planned to expand the number of coal plants to compensate for the pending withdrawal from nuclear power. There are still about 20,000 jobs directly dependent on the coal industry and 40,000 indirectly tied to it.

Cheap and abundant, coal is the world’s leading source of energy to produce electricity and will remain so despite Germany’s exit.

The panel that made the recommendation to close coal plants included leaders in the federal and state governments along with top industry and union representatives, scientists and environmentalists.

Germany long saw itself as a global leader in fighting climate change but was forced to concede in recent years that it would by miss its target date of 2020 to reduce CO2 emissions by 40% from 1990. It is expected to be 32% below 1990 levels by next year.

Germany and nearly 200 nations around the world agreed to the landmark Paris climate accord in 2015 to work to keep global warming 'well below' 2 degrees Celsius and pursue efforts to limit the rise to 1.5 degrees. The planet has already warmed by about 1 degree Celsius since pre-industrial times as a result of the human-caused build-up of greenhouse gases. Scientists say the world is already experiencing the consequences in the form of rising sea levels, more intense hurricanes and wildfires.

Despite its stumbles in recent years that led critics to accuse Germany of hypocrisy, Kemfert said Saturday’s decision will make it likely that Germany can meet the target of a 55% reduction from 1990 CO2 levels by 2030 and an 80% reduction by 2050.”
https://www.fafcosolar.com/solar-news/germany-fights-against-climate-change/

“Germany gets more than a third of its electricity from burning coal, generating large amounts of greenhouse gases that contribute to global warming.”
https://www.apnews.com/3887fa40ea4a4d4fab721c3779a1bec9
 
“Shuttering the rest of Germany’s coal-fired power capacity could cost taxpayers another $2.3 billion per year, The Financial Times reported. The government commission recommended policies to shield ratepayers from cost increases, but it’s unclear if that could realistically be done.

If all goes to plan, Germany will decrease its coal capacity from roughly 42 gigawatts today to 30 gigawatts by the end of 2022, then to 17 gigawatts by 2030. By 2038, all Germany’s coal plants will be closed, according to the plan.”
https://dailycaller.com/2019/01/28/germany-coal-plants-closing-global-warming/
 
The following 1:45 minute video provides an overview of Germany’s plan:
https://www.youtube.com/watch?v=IWaU9l_1sUE
 
*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!




0 Comments

Methods to increase ammonia production

5/3/2019

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 !

“Global food production requires ammonia-based fertilizers. The industrial transformation of atmospheric nitrogen gas (N2, also known as dinitrogen) into ammonia (NH3) is therefore essential for human life. Despite the simplicity of the molecules involved, the cleavage of the strong nitrogen–nitrogen triple bond (the N≡N bond) in dinitrogen and the concomitant formation of nitrogen–hydrogen (N–H) bonds poses a difficult challenge for catalytic chemistry, and typically involves conditions that are costly in terms of energy requirements: high reaction temperatures, high pressures or combinations of reactive reagents that are difficult to handle and energy-intensive to make. …

Motivated by a looming global fertilizer shortage at the turn of the twentieth century, and later by munitions shortages (ammonia can be used to make explosives), the chemists Fritz Haber and Carl Bosch were the first to demonstrate that dinitrogen could be ‘pulled from air’ and converted to ammonia. In the modern’version of the Haber–Bosch process, dinitrogen and hydrogen gas are combined over a catalyst typically based on iron to produce ammonia. Today, global ammonia production occurs at a rate of about 250–300 tonnes per minute, and provides fertilizers that support nearly 60% of the planet’s population. …

Writing in Nature, Ashida et al. demonstrate that a samarium compound mixed with water and combined with a molybdenum catalyst can promote ammonia synthesis from dinitrogen under ambient conditions. The work opens up avenues of research in the hunt for ammonia-making processes that operate under ambient conditions, and raises the question of what an ideal process should be. …

The modern conditions for ammonia synthesis involve temperatures greater than 400 °C and pressures of approximately 400 atmospheres, and are therefore often said to be ‘harsh’. This common misconception has motivated chemists to find ‘milder’ alternatives that use new catalysts to lower the operating temperatures and pressures. In reality, the search for new catalysts should be inspired by the need to reduce the capital expenditure associated with building ammonia plants, and by the requirement to reduce carbon emissions — not only from ammonia synthesis itself, but also from production of the hydrogen used in the process. “
https://www.nature.com/articles/d41586-019-01213-7
 
Another method to produce ammonia has been developed at the University of Tokyo (UTokyo).  “Ammonia -- a colorless gas essential for things like fertilizer -- can be made by a new process which is far cleaner, easier and cheaper than the current leading method. UTokyo researchers use readily available lab equipment, recyclable chemicals and a minimum of energy to produce ammonia. Their Samarium-Water Ammonia Production (SWAP) process promises to scale down ammonia production and improve access to ammonia fertilizer to farmers everywhere. …

The Haber-Bosch process only converts 10 percent of its source material per cycle so needs to run multiple times to use it all up. One of these source materials is hydrogen (H2) produced using fossil fuels. This is chemically combined with nitrogen (N2) at temperatures of about 400-600 degrees Celsius and pressures of about 100-200 atmospheres, also at great energy cost. …

 ‘Worldwide, the Haber-Bosch process consumes 3 to 5 percent of all natural gas produced, around 1 or 2 percent of the world's entire energy supply,’ explained Nishibayashi. ‘In contrast, leguminous plants have symbiotic nitrogen-fixing bacteria that produce ammonia at atmospheric temperatures and pressures. We isolated this mechanism and reverse engineered its functional component -- nitrogenase.’

Over many years, Nishibayashi and his team used lab-made catalysts to try and reproduce the way nitrogenase behaves. Others have tried but their catalysts only produce dozens to several hundred ammonia molecules before they expire. Nishibayashi's special molybdenum-based catalyst produces 4,350 ammonia molecules in about four hours before it expires.

‘Our SWAP process creates ammonia at 300-500 times the rate of the Haber-Bosch process and at 90 percent efficiency,’ continued Nishibayashi. ‘Factor in the gargantuan energy savings in the process and sourcing of raw materials and the benefits really show.’

Anyone with the proper source materials can perform SWAP on a table-top chemistry lab, whereas the Haber-Bosch process requires large-scale industrial equipment. This could afford access to those who lack the capital to invest in such large, expensive equipment. The raw materials themselves are a huge saving in terms of cost. …

SWAP takes in nitrogen (N2) from the air -- as the Haber-Bosch process does -- but the special molybdenum-based catalyst combines this with protons (H+) from water and electrons (e-) from samarium (SmI2). Samarium -- also known as Kagan's reagent -- is currently mined and is used up in the SWAP process. However samarium can be recycled with electricity to replenish its lost electrons and researchers aim to use cheap renewable sources for this in the future.
https://www.sciencedaily.com/releases/2019/04/190424153632.htm
 
It is interesting that two methods have recently been developed to improve the efficiency of a chemical process that was discovered in 1913.

Remember to remind your students to look for replication of these methods .
 

You may want to use either or both of these articles as a Homework assignment to show these current developments.
 
*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!

0 Comments

    Author

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

    Archives

    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    January 2014

    Categories

    All

    RSS Feed

Powered by Create your own unique website with customizable templates.