Did You know? (Mathematics and Science Trivia)

Periodic Table Facts

10 PERIODIC TABLE FACTS

The periodic table is a chart that arranges the chemical elements in a useful, logical manner. Elements are listed in order of increasing atomic number, lined up so that elements that exhibit similar properties are arranged in the same row or column as one another. Here are 10 fun facts to boost your knowledge:

1. Although Dmitri Mendeleev is most often cited as the inventor of the modern periodic table, his table was just the first to gain scientific credibility. It wasn't the first table that organized the elements according to periodic properties.

2. There are about 90 elements on the periodic table that occur in nature. All of the other elements are strictly man-made. Some sources state more elements occur naturally because heavy elements may transition between elements as they undergo radioactive decay.

3. Technetium was the first element to be made artificially. It is the lightest element that has only radioactive isotopes (none are stable).

4. The International Union of Pure Applied Chemistry, IUPAC, revises the periodic table as new data becomes available. At the time of this writing, the most recent version of the periodic table was approved in November 2016.

5. The rows of the periodic table are called periods. An element's period number is the highest unexcited energy level for an electron of that element.

6. Columns of elements help to distinguish groups in the periodic table. Elements within a group share several common properties and often have the same outer electron arrangement.

7. Most of the elements on the periodic table are metals. The alkali metals, alkaline earths, basic metals, transition metals, lanthanides, and actinides all are groups of metals.

8. The present periodic table has room for 118 elements. Elements aren't discovered or created in order of atomic number. Scientists are working on creating and verifying element 120, which will change the appearance of the table. Most likely, element 120 will be positioned directly below radium. It's possible that chemists will create much heavier elements that may be more stable because of special properties of certain combinations of proton and neutron numbers.

9. Although you might expect atoms of an element to get larger as their atomic number increases, this does not always occur because the size of an atom is determined by the diameter of its electron shell. In fact, element atoms usually decrease in size as you move from left to right across a row.

10. The main difference between the modern periodic table and Mendeleev's periodic table is that Mendeleev's table arranged the elements in order of increasing atomic weight, while the modern table orders the elements by increasing atomic number. For the most part, the order of the elements is the same between both tables, but there are exceptions.

Source: https://www.thoughtco.com/important-periodic-table-facts-608854