Read the statements and decide whether they are true (T) or false (F). Correct the wrong statements
1.There are 13 vertical columns in the periodic table.
2. Atomic number of an element is the number of proton found in the nucleus of the atom of that element.
3. The temperature at which an element changes its state from solid to liquid is called as melting point of the element.
4. All elements in a group have different chemical and physical properties.
5. Group 1 on extreme left position contains alkaline earth metals.
Match the elements with their symbols
- Carbon a. Fe
- Oxygen b. Au
- Neon c. Cu
- Iron d. C
- Silver e. K
- Gold f. Ag
- Copper g. N
- Potassium h. O
- Nitrogen i. Mg
- Magnesium j. Ne
Draw the symbols of the elements and translate them
1. Nitrogen atomic number 7 _______________
2. Oxygen atomic number 8 _______________
3. Magnesium atomic number 12 _______________
4. Potassium atomic number 19 _______________
5. Iron atomic number 26 _______________
6. Neon atomic number 10 _______________
7. Argon atomic number 18 _______________
8.Goldatomic number 79 _______________
9.Silveratomic number 47 _______________
10. Carbon atomic number 6 ________________
Periodic Table – some facts.
Read the text and answer the questions.
History
The periodic table was created in 1869 by the Russian scientist Dmitri Mendeleev. Although at that time not all of the world's elements had been discovered, Mendeleev's system for categorizing and arranging the elements by characteristics and atomic number is still in use today.
Most Abundant
Making up about 90 percent of the world by weight, the most abundant element in the universe is hydrogen. It is also the lightest of all the elements and, being found in all organic compounds, is essential to all forms of life.
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Most Compounds
Carbon has almost 10 million known compounds, which is many times more than any other element. Some of the most common carbon compounds are carbon dioxide, carbon monoxide, chloroform, methane and acetic acid. There are so many carbon compounds that an entire branch of science has been dedicated to their study called organic chemistry.
Least Abundant
Francium is one of the rarest elements in the world and results from the breakdown and decay of actinium. It has an extremely short half-life (a matter of minutes), and scientists estimate that there is no more than a few ounces of Francium in existence on the Earth at any given time.
Most Surprising
Oxygen is the third most abundant element in the universe and is highly reactive, meaning it likes to pair and form compounds with most other elements. In its pure liquid or solid state, oxygen is a pale shade of blue. Although oxygen is best known for being part of our atmosphere and is 21 percent of the air we breathe, it is actually even more common in the Earth's crust--making up almost half of it. It also makes up about 66 percent of the human body and 90 percent of water, as well as makes up the Earth's protective shield, the ozone layer.
Updates
Elements are added to the periodic table as they are discovered. The table originally started with 65 elements. The periodic table was last reviewed and accepted by the Union of Pure Applied Chemistry (IUPAC) in 1985.
According to CNN, “elements 113, 115, 117 and 118 have formally been recognized by the International Union of Pure and Applied Chemistry (IUPAC), the U.S.-based world authority on chemistry.” The announcement was made December 30th and means that the seventh row of the table is finally complete.
Elements 115, 117 and 118 came from a Russian-American team at the Joint Institute for Nuclear Research in Dubna and Lawrence Livermore National Laboratory in California, while Japanese researchers were credited for 113.
None of the elements were found in nature, but instead created in a laboratory. According to CNN, “the elements had temporary names and symbols on the periodic table as their existence was hard to prove. Since they decay extremely quickly, scientists found it difficult to reproduce them more than once.”
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He continues, “IUPAC has now initiated the process of formalizing names and symbols for these elements temporarily named as ununtrium, (Uut or element 113), ununpentium (Uup, element 115), ununseptium (Uus, element 117), and ununoctium (Uuo, element 118).”
The table has not been updated since 2011, when elements 114 (Flerovium) and 116 (Livermorium) were added to the family.
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