2003 Virginia SOLs
An element is the smallest part of matter that cannot be broken down into simpler forms by chemical means. In the early 19th century, scientists began to arrange elements according to similar physical and chemical properties. The scientist who had the greatest success with this was Dmitri Medeleev, a Russian chemist. He arranged the elements according to increasing atomic mass, as well as in columns according to similar properties. In this way, he was able to predict elements that were as yet undiscovered through the gaps in his chart. In the early 1900's, Henri Mosely improved Medeleev's periodic table by arranging it according to similar properties as well as increasing atomic number.
Today's periodic table is arranged according to increasing atomic number and increasing atomic mass (for the most part). It can also be categorized according to the location of metals (the left side of the table), non-metals (the right side of the table), and metalloids (elements that exhibit the properties of both metals and non-metals). For example, some metalloids are poor conductors of electricity at low temperatures, but when heated, they become very good conductors. The metalloid elements are Si, Ge, As, Sb, Te, Po, and At.
The table has 7 periods, or horizontal rows, and 18 groups or families. The groups are the vertical columns. If you look closely at the periods, you will see that all of the elements in a period have the same number of electron energy levels. The first period has 1 electron energy level, the second period has 2 electron energy levels, etc. There is a pattern in the groups as well. All of the elements in group 1 have 1 electron in their outer energy level. All of the elements in group 2 have 2 electrons in their outer energy level; the elements in group 13 have 3 electrons in their outer energy level; the elements in group 14 have 4 electrons in their outer energy level, etc. You might have noticed that groups 3-12 were not included in the trend. That is because they are the transition elements, and the transition elements follow a slightly different trend due to the overlap of energy levels and the way those energy levels fill. The number of electrons in the outer energy level determines the element's chemical properties. Therefore, since all of the elements of a group have the same number of electrons, they will react similarly to each other. The elements in the first group have a special name; they are called the alkali metals. The alkali metals are the most reactive group of metals on the periodic table. Francium is the most reactive of the group; reactivity increases as you go from the top to the bottom of this column.
Group 17 also has a special name. This is the halogen group. The halogen group is the most reactive non-metal group on the periodic table. Fluorine is the most reactive non-metal in this group, and reactivity decreases as you go from the top of the column to the bottom.
Group 18 is known as the noble gas or inert gas group. It has been named this because all of its elements are stable, and unlikely to react or bond with other elements. Notice that all of these elements have 8 electrons in their outer shell (with the exception of He that only has 2 electrons in its outer energy level. This, however, is not really an exception as Helium's single energy level (unexcited) can only hold a maximum of 2 electrons.)
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For a copy of a blank periodic table chart, click here.
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You are a part of a collection of scientists who have been chosen to assist a group of alien scientists. In order to be able to converse scientifically, you must learn their language, and most importantly, you must arrange their elements according to the trends that exist in the periodic table. Below are clues for the alien's elements. So far, the aliens have only discovered elements in groups 1, 2, and 13-18, and periods 1-5. Although the names of the elements are different, they must correspond to our elements if our belief of universal elements holds true. Read each clue carefully, and then place the symbol for that clue's element in the blank periodic table provided.
1. Livium (Lv): This element is responsible for life. It has 2 electron energy levels and 4 electrons available for bonding in the outermost energy level.
2. Computerchipium (Cc): This element is important for its use as a semiconductor in computers.
3. Lightium (L): This is the lightest of elements; aliens previously used it in their aircraft until their aircraft caught fire in a horrific accident.
4. Breathium(Br): When combined with Lightium (L), it makes the alien's most common liquid whose formula is L2 Br.
5. Francium (F): A metal found in period 4 group 13.
6. Moonium (Mo): An element with an atomic number of 34.
7. Explodium (Ex): This element is the most reactive metal on the alien's table.
8. Violetium(V): This element is found as part of a compound in bananas. When burned, it has a violet colored flame.
9. Sparkium (Sp) and Burnium (Bu) are members of the alkali metal group, along with Violetium(V) and Explodium (Ex). Their reactivity, from least to greatest, is Sp, Bu, V, Ex.
10. Balloonium (Ba): A noble gas used to fill balloons.
11. Toothium (To): This element is added to juices to help build strong bones and teeth.
12. Metalloidium (M) and Poisonium (Po): Two metalloids found in period 4. Po is more massive than M.
13. Lowigium (Lo): A period 4 halogen.
14. Darkbluium(Dk): Has an atomic mass of 115.
15. Hugium (Hu): The element on the alien's periodic table that has the most mass.
16. Glucinium (Gl): The element found in period 2, group 2.
17. Reactinium (Re): The most reactive non-metal on the periodic table.
18. Balloonium (Ba), Signium(Si), Stableium(Sb), Supermanium (Sm), and Hugium (Hu) are all noble gases. They are arranged above from least to most massive.
19. Cannium (Cn): This element helps to preserve foods; it is used in can manufacturing.
20. Burnium (Bu), Blue-whitium (Bw), Bauxitium (Xi), Computerchipsium (Cc), Bringer-of-lightium (Bl), Stinkium (Sk), Purium (P), and Stableium (Sb) are all found in period 3. Bu has 1 electron in its outer energy level, Bw has 2, Xi has 3, Cc has 4, Bl has 5, Sk has 6, P has 7 and Sb has 8.
21. Scottishium (Sc): A metal element found in group 2.
22. Infectium (If): This element, mixed with alcohol, is used on cuts.
23. Abundantcium(Ab): One of the most abundant gasses in the universe. It has 7 protons, 7 neutrons, and 7 electrons.
24. Some additional clues: The number after the symbol indicates the number of electrons in the outer energy level: Notalonium(Na): 5, Earthium (E): 6, Boracium (B): 3.
For above average students, allow the students to make their own clues about the elements on the periodic table. Students should develop their own names and symbols for the elements, and research the elements for their clues. Suggest that students create periodic table based clues (i.e.: This element is found in period 3 group 2.), creative clues (i.e.: This element was found on a metal man in the Wizard of Oz.), and descriptive clues (i.e.: This is a metal that will melt in your hand and expands upon freezing.) Allow students access to the internet and books about elements. When students have created their clues, have them exchange their project with another student in the class to see if they can solve the puzzle. Students could even be given a rubric to grade the work of others in the class.
Students with Special Needs
All students should be able to participate in this activity.
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Blank Periodic Chart: