Relationships Among Elements

1.)  Look at the shape of your graph.  Wat patterns do you observe?
           I observe that it starts out high, then makes a major drop, then goes up higher than before, and slides back down.  Then, the line goes even higher than before, and again, it goes back down.

2.)  What family is represented by the high peaks in your graph?
          The alkaline metal family is represented by the peaks in my graph. 

3.)  What family is represented by the low points in your graph?  
          Group 17 (fluorine, chlorine, etc) is represented by the low points of the graph.


4.)  What family is represented by the smaller peaks just before the high peaks in your graph?
         The noble gasses are represented by the smaller peaks.


5.)  What trends do you notice about the radii of the elements at the high peaks as you move from left to right on your graph?  Look at your periodic table and find the element that represents each peak.  What does each high peak begin in the periodic table?  
          The radii of the elements at the high peaks grow bigger.  Each high peak represents a new period.  The first peak represents sodium, the second one potassium, the third rubidium, and it goes on down the alkaline metal family.  On the periodic table, all of these elements are on the column in the far right.  They all start new periods.


6.)  What happens to the radii of the elements between the two highest peaks? What does each of these groups of elements represent?
         The radii of the elements in between the two highest peaks get smaller one at a time.  They go 126, 125, 124, 123, 122, 121, etc.  Each of these groups of elements represents a new column. 

Going Further:
How can a graph such as the one you made help to predict the properties of elements that have not been discovered yet?  How reliable do you think this would be?  Explain.
          A graph such as the one I made can help you predict the properties of elements that have not been discovered yet because it follows a pattern.  When graphs follows patterns, you can predict things.  My graph repeatedly goes up and down and up down.  This means it will probably continue rising and dropping, so we can predict that un-discovered elements will have atomic radiuses that are either higher or lower, depending on where they are in the periodic table.  This would be semi-reliable, but you wouldn't be able to use a graph like this for exact precision.  Although the graph consistently follows a pattern, it does have unpredictable numbers.  If you wanted to estimate around how large the atomic radius of an unknown element was, you could do it, but if you wanted exact answers, you would have a very hard time doing it with just a graph. 

Discover:
How do the radii of metals in each period compare to the radii of nonmetals in the period? 
          The radii of metals in each period are much larger than those of the nonmetals in the same period.  For example, sodium and magnesium (metals) have radii of 186 and 127 picometers, whereas sulfur and chlorine (nonmetals) only have radii of 103 and 91 picometers.
         

Current Events: LREE found in Afghanistan

          According to American geologists, there could be around 1 million metric tons of LREE in the Khanneshin carbonatite found in Afghanistan. LREE is the acronym for "light rare earth elements."  Elements such as cerium, lanthanum, neodymium, are all very rare, and mining for and selling these minerals could help Afghanistan's economy.  Also, there is an estimate that 1.5 million metric tonnes of REE (rare earth element) may also be found in southern Afghanistan.  Contrary to the name, rare earth elements aren't actually that rare.  Some of them are quite abundant in the Earth's crust.  However, it is difficult to find any deposits of REE large enough to extract from the earth without spending too much money.  REE are becoming increasingly important materials when making things such as batteries and high-strength magnets.  REE are also essential ingredients for us to make "green" alternative energy sources.  We need REE to create electric cars, wind power, and solar cells.  These huge deposits of LREE and REE could give Afghanistan an economically bright future.

For more information, go to: Elements in Afghanistan

Elements Video

The Periodic Table of Elements

Metals vs Nonmetals Periodic Table

Current Events - Mining in Mongolia

Copper Ore

          There is a huge mining operation currently going on in the Gobi Desert on "Oyu Togoi" which means "Turquoise Hill."  They are finding tons of copper and gold in the Desert.  It is estimated that that mine will produce around 300,000 ounces of gold and 450,000 tons of copper, and will probably end up being one-third of "the nation's total economic output."  Apparently, there is so much metal down there that the company will be busy for at 50 years or more.  The average amount of pay for Mongolia will increase by around 50%.  However, although the mining is doing so much good for the country, it is proving difficult for the local nomads to live their lives.  Some people are afraid that the mining will use up all the water in the ground, and others are frustrated because there is a limited amount of space where they can graze their herds.  Yet other nomadic herders believe that the mine is a good opportunity for making money.  If they can work at the mine and herd their animals, their children will have better chances to go to school and live better lives.

Gold

          I think that this mining company is doing a pretty good job of making Mongolia money and creating jobs for people who would otherwise be unable to support themselves.  The local people know that they need jobs, and even though it can be hard for the herders, I think that overall, the mines will benefit the country and its people more than it will hurt them. 

For more information, go to:  Mining in Mongolia

Discovering which Substance is which

          During this lab, my group was given three cubes (all different elements/compounds), and we had to discover what they were made of using the mass, length, width, and height of the cubes.  To figure out what kinds of materials we had, we needed to figure out the density of each cube.  The density of something is the mass of the object divided by its volume (D = m/V).  That meant that we had to work out the volume of each cube.  Luckily each cube was exactly the same size, and since volume is length times width times height (L*W*H), all we had to do was measure one side of each cube and cube it.  All the sides of each cube were 2.5 cm long, so we cubed 2.5 cm and got a volume for each as 15.625 cm cubed.  We then measured the mass of each cube and divided them by 15.625 to get their densities.  Here are our results:

• Cube I:   0.6976 g/cm cubed
• Cube II: 0.9664 g/cm cubed
• Cube III: 1.504 g/cm cubed

Then, we looked at our charts and, according to density, Cube I was made of oak; Cube II was Polypropylene; Cube III was PVC.  

PVC

Oak

Polypropylene

          Of course, there were many places where we could have made mistakes.  There could have been flaws in the cubes themselves.  There might have been mistakes in the Balance we used to measure the mass of the cubes.  The rulers we needed to measure the sides of the cubes could have been incorrect.  We could have done something wrong.  This means that the results above are not completely accurate.  There are probably errors that have altered the numbers above.  In order to fix this, we could make sure the Balance and rulers are as accurate as possible.  We still would not be able to get everything completely right, but we could get pretty close.