How to set a quiz in seconds

Use AUS-e-TUTE's quiz wizards to set a quiz in seconds ...



Visit www.ausetute.com.au for more information.

How to make a worksheet

How simple is it to make a worksheet at AUS-e-TUTE?



http://www.ausetute.com.au

Magnetic Detergent

Scientists have long been searching for a way to control surfactants once they are in solution to increase their ability to dissolve oils in water and then remove them from a system. Surfactants sensitive to light, carbon dioxide or changes in pH, temperature or pressure have all been investigated. Bristol University scientists have produced the world's first magnetic surfactant by dissolving iron in inert detergents composed of chloride and bromide ions. The addition of the iron creates magnetic centres within the detergent particles.

To test the properties of their magnetic detergent, the scientists introduced a magnet to a test tube containing their new detergent lying beneath a less dense organic solution. When the magnet was introduced the iron-rich detergent overcame both gravity and surface tension between the water and oil, to levitate through the organic solvent and reach the source of the magnetic energy, demonstrating its magnetic properties.

Commercial development of magnetic detergents could be a big bonus for the environment. In the future oil spills could be cleaned up using magnetic detergents, and the oildetergent mixture removed using magnets.

Reference
Paul Brown, Alexey Bushmelev, Craig P. Butts, Jing Cheng, Julian Eastoe, Isabelle Grillo, Richard K. Heenan, Annette M. Schmidt. Magnetic Control over Liquid Surface Properties with Responsive Surfactants. Angewandte Chemie International Edition, 2012; DOI: 10.1002/anie.201108010

Further Reading
Soaps and Saponification
Detergents
Transition Metals
Ligands and Complex Ions

Suggested Study Questions

1. What other elements, besides iron, could be used to produce magnetic detergents?
   
2. Use the concept of the micelle to explain how iron can create magnetic centres within these new detergent mixtures.
3. For the experiment described in the second paragraph,
   
   • write a suitable aim
   • write a suitable method (procedure)
   • draw the results of the experiment as described
   • write a suitable conclusion
4. You have been asked to determine the effectiveness of this new magnetic detergent at different pH levels.
   • Write a suitable hypothesis.
     
   • If you were to undertake an experiment to test this hypothesis, what variables would need to be controlled?
     

5. You have been asked to determine the effectiveness of this new magnetic detergent at different pH levels.

   • write a suitable aim
   • write a suitable method (procedure)

6. Surfactants sensitive to light, carbon dioxide or changes in pH, temperature or pressure have all been investigated. Why do you think that a magnetic surfactant might be a better alternative for cleaning up oil spills in natural waterways?

7. What disadvantages can you see in using magnetic surfactants in cleaning up oil spills?
   

   
   
   
   

4 Water Experiments to Download

The International Year of Chemistry may be over, but you can still contribute to the Global Experiment until the end of March.

There are 4 experiments to conduct using water:

1. Acidity
2. Salinity
3. Build a water filtration unit using household materials
4. Using solar energy to purify water

You can download the details of all 4 experiments at

http://water.chemistry2011.org/web/iyc/experiments

You will be able to conduct the 4 experiments in class and submit your results to the website until 31^st March.

Even if you can't upload your results to the website, the 4 experiments above make a terrific teaching and learning resource for the future!

2012 Chemistry Calendar

The quintessential 2012 chemistry calendar is now available for download from ausetute.com.au

Now there's no excuse for forgetting to celebrate the birthday of some celebrated chemists !

Flerovium and Livermorium?

Elements 114 and 116 are the latest additions to the Periodic Table of the elements,
created by smashing calcium ions into a curium target to create element 116. Element 116 decayed almost immediately into element 114. The scientists also created element 114 separately by replacing curium with a plutonium target.
Both elements were first produced at the Joint Institute for Nuclear Reasearch, Dubna, Russia, and Lawrence Livermore chemists. Element 114 was first produced in 1998 and element 116 in 2000. The proposed name for element 114 is flerovium with the symbol Fl, and, the proposed name for element 116 is livermorium with the symbol Lv.

Flerovium was chosen to honour the Flerov Laboratory of Nuclear Reactions where element 114 was synthesized. The laboratory itself is named after Georgiy N. Flerov (1913-1990) , a renowned physicist who discovered the spontaneous fission of uranium and was a pioneer in heavy-ion physics. He is the founder of the Joint Institute for Nuclear Research.

Livermorium was chosen to honour Lawrence Livermore National Laboratory (LLNL) and the city of Livermore, California. A group of researchers from the Laboratory, along with scientists at the Flerov Laboratory of Nuclear Reactions, participated in the work carried out in Dubna on the synthesis of superheavy elements, including element 116. The element lawrencium, element 103, was named after LLNL's founder E.O. Lawrence.

The new names were submitted to the IUPAC in October 2011 and now remain in the public domain. The new names will not be official until about March 2012 when the public comment period is over.

Reference
DOE/Lawrence Livermore National Laboratory (2011, December 1). Scientists propose new names for elements 114 and 116. ScienceDaily. Retrieved December 11, 2011, from http://www.sciencedaily.com­ /releases/2011/12/111201125400.htm

Further Reading
History of the Elements
Periodic Table of the Elements
Isotopes
Nuclear Decay

Suggested Study Questions

1. What is the atomic number of each of the following elements?
   
   • calcium
   • curium
   • plutonium
   • uranium
   • lawrencium
     
   • flerovium
   • livermorium
2. How many protons are in the nucleus of an atom of each of the following elements?
   
   • calcium
   • curium
   • plutonium
   • uranium
   • lawrencium
     
   • flerovium
   • livermorium
3. Calculate the number of electrons present in an atom of each of the following elements:
   
   • calcium
   • curium
   • plutonium
   • uranium
   • lawrencium
     
   • flerovium
   • livermorium
4. For each of the elements above, state whether it is found in nature or whether it is man-made.
   
5. Assuming each of the elements above forms an ion with a charge of +2 then
   • how many electrons will be present in each ion?
   • how many protons will be present in each ion?

6. Write a possible nuclear equation to show the production of livermorium from calcium ions and curium atoms.

7. Write a possible nuclear equation to show the production of flerovium from plutonium atoms and calcium atoms.

8. Write a possible nuclear decay equation to show how livermorium could decay to produce flerovium.

9. The suggested symbol for Flerovium is Fl. List all other elements that have a symbol which includes the letter F.

10. The suggested symbol for Livermorium is Lv. List all the other elements that have a symbol which includes the letter L.
    

    
    

Liquid Chlorine?

What is wrong with this picture?

Is it possible for an ordinary plastic bottle with a screw cap to contain liquid chlorine?
Probably not!

Chlorine exists as a diatomic yellow-green gas at room temperature and pressure, that is, chlorine exists as Cl_2(g).
In order to produce liquid chlorine we could:

• lower the temperature of the bottle to change the gas into a liquid at atmospheric pressure.
• raise the pressure within the bottle to change the gas into a liquid at room temperature.
• lower the temperature and raise the pressure at the same time.
  

At 1 atmosphere pressure, the melting point of chlorine is about -101^oC and its boiling point is about -34^oC. So, chlorine will be a liquid at temperatures between -34^oC and -101^oC.
For comparison, your refrigerator is probably set to maintain a temperature of about 4^oC while the freezer has a temperature of around 0^oC, not cold enough to liquefy chlorine! A plastic bottle sitting on the shelf in your garage is not going to be cold enough to store chlorine as a liquid!

Gaseous chlorine could also be changed into a liquid by applying pressure. At room temperature this can be achieved with a pressure about 8 times that of atmospheric pressure, which is highly unlikely to occur in our plastic bottle with the screw cap.

So, the fluid in the plastic bottle labelled "liquid chlorine" is not chlorine. What is it?
It is most likely to be an aqueous solution of sodium hypochlorite, NaClO_(aq).
Aqueous solutions of sodium hypochlorite are produced by bubbling chlorine gas, Cl_2(g), through an aqueous solution of sodium hydroxide, NaOH_(aq) at room tmeperature:
Cl_2(g) + 2NaOH_(aq) → NaClO_(aq) + NaCl_(aq) + H₂O_(l)
When the aqueous sodium hypochlorite solution is mixed with dilute acid, chlorine gas is released:
2H⁺_(aq) + OCl^-_(aq) + Cl^-_(aq) → Cl_2(g) + H₂O_(l)

The chlorine gas that is released can kill bacteria and other microbes, so aqueous solutions of hypochlorites are often used as disinfectants.

Further Reading
Chemical and Physical Changes
Kinetic Theory of Gases

Suggested Study Questions:

1. Identify each of the changes below as either a chemical change or a physical change:
   • freezing water in a freezer
   • boiling water in a kettle
   • cooling chlorine gas to make chlorine liquid
   • boiling liquid chlorine to make chlorine gas
   • bubbling liquid chlorine though aqueous sodium hydroxide solution to form a solution of sodium hypochlorite
     
   • bubbling chlorine gas through water to make hypochlorous acid
2. Name each of the physical changes above.
3. Use the kinetic theory of matter to explain what happens to chlorine molecules when:
   • chlorine gas is cooled to produce liquid chlorine at 1 atm pressure
     
   • chlorine gas is subjected to a pressure of more than 8 atmospheres at 25^oC
   • chlorine gas is cooled to 4^oC
4. Sodium hydroxide has a melting point of 319^oC and a boiling point of 1390^oC at 1 atm pressure. Describe how you could produce sodium hydroxide liquid.
5. Which of the following pure substances could be kept in an ordinary plastic bottle with a screw cap on a shelf in your garage?
   
   • ozone (melting point -192^oC, boiling point -110⁰C)
   • potassium chloride (melting point 772^oC, boiling point 1407^oC)
   • sulfur dioxide (melting point -75^oC, boiling point -10^oC)
   • ethanol (melting point -114^oC, boiling point 78^oC)