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world's oldest periodic table

1/25/2019

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The era of Easy recycling may be at an end

1/18/2019

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Graphene water filter for ocean water

1/11/2019

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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 !

“Approximately 783 million people, or 11 percent of humans on the planet, live without access to clean water for drinking, irrigation, and hundreds of other uses. Researchers in the United Kingdom seek to solve that problem. They have created a graphene sleeve out of carbon that can filter and desalinate ocean water, making it drinkable and effectively solving our freshwater crisis.

Large-scale desalination plants have been around for years, sure. But they’re pricey, not real great for the environment, and can actually hurt marine life. These graphene sieves? Not so much.”
https://www.ft.com/content/d768030e-d8ec-11e7-9504-59efdb70e12f

“Graphene is an allotrope (form) of carbon consisting of a single layer of carbon atoms arranged in a hexagonal lattice. It is a semimetal with small overlap between the valence and the conduction bands (zero bandgap material). It is the basic structural element of many other allotropes of carbon, such as graphite, diamond, charcoal, carbon nanotubes and fullerenes. ...

It can be considered as an indefinitely large aromatic molecule, the ultimate case of the family of flat polycyclic aromatic hydrocarbons.

Graphene has many uncommon properties. It is the strongest material ever tested, conducts heat and electricity efficiently, and is nearly transparent.

Graphene shows a large and nonlinear diamagnetism, greater than that of graphite, and can be levitated by neodymium magnets.

Scientists theorized about graphene for years. It had been produced unintentionally in small quantities for centuries through the use of pencils and other similar graphite applications. It was observed originally in electron microscopes in 1962, but it was studied only while supported on metal surfaces. The material was later rediscovered, isolated, and characterized in 2004 by Andre Geim and Konstantin Novoselov at the University of Manchester. Research was informed by existing theoretical descriptions of its composition, structure, and properties. This work resulted in the two winning the Nobel Prize in Physics in 2010’ ‘for groundbreaking experiments regarding the two-dimensional material graphene.’ “
https://en.wikipedia.org/wiki/Graphene

“A UK-based team of researchers [in April 2017] has created a graphene-based sieve capable of removing salt from seawater.

The sought-after development could aid the millions of people without ready access to clean drinking water.
The promising graphene oxide sieve could be highly efficient at filtering salts, and will now be tested against existing desalination membranes.

It has previously been difficult to manufacture graphene-based barriers on an industrial scale.

Reporting their results in the journal Nature Nanotechnology, scientists from the University of Manchester, led by Dr Rahul Nair, show how they solved some of the challenges by using a chemical derivative called graphene oxide.

Isolated and characterised by a University of Manchester-led team in 2004, graphene comprises a single layer of carbon atoms arranged in a hexagonal lattice. Its unusual properties, such as extraordinary tensile strength and electrical conductivity, have earmarked it as one of the most promising materials for future applications.

But it has been difficult to produce large quantities of single-layer graphene using existing methods, such as chemical vapour deposition (CVD). Current production routes are also quite costly. “
https://www.bbc.com/news/science-environment-39482342

“Graphene-oxide membranes have long been considered a promising candidate for filtration and desalination, but although many teams have developed membranes that could sieve large particles out of water, getting rid of salt requires even smaller sieves that scientists have struggled to create.

One big issue is that, when graphene-oxide membranes are immersed in water, they swell up, allowing salt particles to flow through the engorged pores.

The Manchester team overcame this by building walls of epoxy resin on either side of the graphene oxide membrane, stopping it from swelling up in water.

This allowed them to precisely control the pore size in the membrane, creating holes tiny enough to filter out all common salts from seawater.

The key to this is the fact that when common salts are dissolved in water, they form a 'shell' of water molecules around themselves.”
https://www.sciencealert.com/scientists-create-a-graphene-based-sieve-that-turns-seawater-into-drinking-water

“When the common salts are dissolved in water, they always form a ‘shell’ of water molecules around the salts molecules. This allows the tiny capillaries of the graphene-oxide membranes to block the salt from flowing along with the water. Water molecules are able to pass through the membrane barrier and flow anomalously fast which is ideal for application of these membranes for desalination.

Professor Rahul Nair, at The University of Manchester said: ‘Realisation of scalable membranes with uniform pore size down to atomic scale is a significant step forward and will open new possibilities for improving the efficiency of desalination technology.’ “
https://www.manchester.ac.uk/discover/news/graphene-sieve-turns-seawater-into-drinking-water/

“The graphene-oxide breakthrough has been welcomed by scientists in the field as a promising development, but some are cautious of the next steps.

‘The selective separation of water molecules from ions by physical restriction of interlayer spacing opens the door to the synthesis of inexpensive membranes for desalination,’ wrote Ram Devanathan of the Pacific Northwest National Laboratory, in an accompanying news-and-views article in the journal.

More work still needs to be done to test the durability of the barriers and to confirm the membrane is resistant to ‘fouling by organics, salt and biological material,’ he said.

Water treatment with membranes that separate water molecules from ions, pathogens and pollutants has been proposed as an energy-efficient solution to the freshwater crisis, Devanathan added.

‘The ultimate goal is to create a filtration device that will produce potable water from seawater or waste water with minimal energy input.’ “
https://www.cnn.com/2017/04/04/health/graphene-sieve-drinkable-seawater/index.html

Past Ocean Water blog posts include:

05/25/2018   Students Invent Filter for Water Purification

07/27/2018   Invention for Water Conservation

08/10/2018   Oil Spill Sponge

You may have Midterm Examinations coming up, so for your reference:

01/04/2015     Midterm Examinations

*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 week!

0 Comments

china is a renewable energy champion

1/4/2019

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 !

Happy New Year 2019!

“DATONG, China – [According to a 10/9/17 article,}, Scott Pruitt, the head of the U.S. Environmental Protection Agency, declared Monday that ‘the war on coal is over.’ He told an audience in Kentucky that he plans to repeal an Obama-era rule that limits carbon emissions from power plants that burn coal.

China, on the other hand, is doing the opposite. Coal is on the way out and solar power is coming in.
On a farm in northern China, they are planting a new crop: Nearly 200,000 solar panels in the heart of coal country.
In the south, China flipped the switch on the world's largest floating solar installation -- built on top of a lake created by an abandoned coal mine. Projects like these helped China double its solar capacity last year. It is now twice as big as the U.S. capacity.”
https://www.cbsnews.com/news/us-moves-toward-coal-china-bets-big-on-solar/

“At present, China leads the world in terms of wind and solar power capacity. And with large-scale industrial applications, the costs have fallen substantially. A good example is photovoltaic (PV) technology: the price of PV modules decreased from about 30 Yuan per watt in 2007 to about 10 Yuan in 2012, and by 2017 it had decreased further to just 2 Yuan per watt.

The success of China's renewable energy drive fully illustrates the effectiveness of China’s on-grid tariff subsidies. The advantage of the on-grid tariff policy - through which the government can make renewable energy production more competitive and attractive to businesses and investors - is that it anchors the revenue of power generation throughout the entire life cycle. In this way, it conveys a clear price signal to investors, and can effectively support the early stages of renewable energy development.”
https://www.weforum.org/agenda/2018/05/china-is-a-renewable-energy-champion-but-its-time-for-a-new-approach/

“China is now the world’s largest backer of green energy, accounting for 17% of global investment in the sector. According to Greenpeace, it installed an average of more than one wind turbine every hour of every day in 2015. It also covered the equivalent of one soccer field with solar panels every hour, action that may allow China to meet its 2020 goals for solar installation two years ahead of schedule. By 2030 it is hoped that cleaner energy will help reduce China’s CO₂ emissions by 54% from 2010 levels.

This is good news because the inescapable fact is that efforts to mitigate climate change are doomed to fail if the Chinese do not get on board. Compared with other countries, China still has a long way to go. Britain, for instance, recently managed a day without coal for the first time in more than 130 years, while other countries have drastically cut their carbon footprint.

However, energy policy is, as with most aspects of Chinese life, more complicated and more susceptible to internal and external pressures than many observers believe. The reaction of the Chinese leadership to these pressures gives us hope that the country can free itself of dirty coal, and that this day may come sooner rather than later.”
https://www.juancole.com/2017/05/chinas-covering-football.html

“Solar is an incredible source of energy and could be an answer to climate change so it’s no surprise that there are lots of incredible facts about solar power and solar technology.
From the weird and wonderful to how solar panels could benefit your day-to-day life, here are our top 10 solar facts…

1. The sun sends more energy to earth in an hour than humans use in a year

430 quintillion (that’s 430 followed by 18 zeros) Joules of energy hits the Earth from the sun every hour while we use 410 quintillion Joules each year. Not only that, the light from the sun carrying the energy only takes around 8 minutes to make the 91 million mile journey.

2. Enough solar panels are installed in China every hour to cover a football pitch

Not only is China adopting solar technology at quite a pace, they’re also coming up with creative ways to install them – Northern China is home to a giant solar panda and Southern China can boast the world’s largest floating solar installation. So it looks like they’ll just keep installing them. Well, until they run out of space…

3. A solar-powered home can reduce CO2 emissions by 100 tons within 30 years

100 tons might sound like a lot and that’s because it is and this statistic even takes into account the energy used to manufacture the solar panels.

4. Charles Fritts developed the first ever solar cell panel in 1883

American inventor, Charles Fritts, is credited with having invented the first solar cell panel by coating selenium with a thin layer of gold. It had an efficiency of 1-2% which looks small compared to the 10-20% efficiency of modern solar panels on UK homes.

5. If we covered a small fraction of the Sahara desert with photovoltaic cells, we could generate all of the world’s electricity requirements

The sun shines brighter on the Sahara Desert than anywhere else on Earth and covering roughly 1% of it in solar panels could meet the electricity requirements of everyone on Earth.

6. Countries now use solar energy to power spaceships

One example is the Mars Observer which used an expandable 6 panel solar array to generate its energy from the sun.

7. In March 2015 the Solar Impulse plane left Abu Dhabi for the first ever round the world trip in an aircraft powered by solar energy

Carrying more than 17,000 solar panels, the Solar Impulse 2 spent 23 days in the air, making 23 stops along the way.

8. Solar panels don’t need direct sunlight to work

Solar panels generate energy from daylight rather than direct sunlight so will work on cloudy days. They just won’t be generating anything during the night but installing a solar battery means that you can still use solar energy during the night.

9. India is home to the world’s largest solar power park which consists of 2.5 million solar panels

Located in Kamuthi, Tamil Nadu, the world’s largest solar park covers 2,500 acres and has a capacity of 648 megawatts which is thought to make enough power for around 750,000 people.

10. You can generate energy together with your local community with a solar garden

Solar gardens or shared renewable energy plants can generate electricity that’s shared around a community which means that you don’t need to have the panels installed on your property.”
https://www.solarguide.co.uk/facts-about-solar#/

“Air pollution isn’t the only reason China is so serious about renewables, but it’s a powerful one. And it was a big part of what put President Xi Jinping in a position to announce, in a landmark 2014 deal with President Obama, that China’s emissions of planet-warming carbon dioxide would peak around 2030, a pledge that became the centerpiece of its commitments under the Paris climate agreement.

It appears now to be ahead of schedule in meeting that goal. Official figures can be unreliable, but they show that coal consumption, the main driver of China’s carbon emissions, fell in 2016 for the third straight year. And because China has clearly decided that cutting coal use—the fuel powers much of its heavy industry as well as providing electricity— is in its own interest, it’s a trend that’s likely to continue even as the United States, under President Trump, abandons Obama’s climate agenda.

Because China accounts for half the world’s coal consumption, that’s good news not just for the health of those who must breathe its air, but also for the wider effort to check runaway global warming.”
https://news.nationalgeographic.com/2017/05/china-renewables-energy-climate-change-pollution-environment/
“The renewables rollout has not been without its troubles. Vast fields of wind turbines have been erected in the country’s sparsely populated northwest, far from the big cities where electricity is most needed, and the construction of transmission lines to move all that power has failed to keep up.

'They set up these huge wind farms and they don’t have connections to the grid,' says Antung Liu of Indiana University Bloomington. 'They just have this attitude that ‘We’ll build it, and hopefully we’ll be able to use it later.'

What’s more, grid operators have shown a bias toward coal production, so renewable power has sometimes gone unused even when the physical connections are there. Greenpeace estimates that 19 percent of Chinese wind power was wasted in the first three quarters of last year.

Leaders are now starting to reckon with those issues, installing new power lines and focusing on building smaller wind and solar farms in populated areas.”

“Anders Hove, a Beijing-based clean energy expert from the Paulson Institute, said that as recently as 2012 solar power was shunned as a potential source of energy for China’s domestic market because it was seen as too expensive.

No more. Costs have since plummeted and by 2020 China – which is now the world’s top clean energy investor – hopes to be producing 110GW of solar power and 210GW of wind power as part of an ambitious plan to slash pollution and emissions. By 2030, China has pledged to increase the amount of energy coming from non-fossil fuels to 20% of the total.

Earlier this month, meanwhile, China’s energy agency vowed to spend more than $360bn on renewable energy sources such as solar and wind by 2020, cutting smog levels, carbon emissions and creating 13m jobs in the process. “
https://www.theguardian.com/environment/2017/jan/19/china-builds-worlds-biggest-solar-farm-in-journey-to-become-green-superpower

Some of these articles are dated in 2017, so your students may want to research more recent articles to see more of what is happening.

Past blog posts include:

03/05/2014      Heat and Energy
06/05/2016      Air Pollution in China
01/13/2017      America's First Offshore Wind Farm
06/16/2017 Source of Energy Choices: An Article
10/26/2018      China Going Solar

You may have Midterm Examinations coming up, so for your reference:
01/04/2015     Midterm Examinations

*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 2019!

0 Comments

world's oldest periodic table

The era of Easy recycling may be at an end

Graphene water filter for ocean water

china is a renewable energy champion

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