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Key video: PERIODIC TABLE IN 2 MINUTES !! 

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Key video: PERIODIC TABLE IN 2 MINUTES !! 

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https://www.youtube.com/watch?v=5-_aBTNavdQ

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They use it in order to predict and understand elements' properties.

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Nonmetals (except hydrogen) are located in the right side of the periodic table. Nonmetals do not conduct thermal energy or electricity. Most of them are gases

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Metals are the most common group in an Element Table. They are usually on the beginning and middle of the table. They all are shiny and conduct electricity and thermal energy.

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A period is a row in the periodic Table. The atomic number increases by 1 in a period. The physical and chemical properties also change.

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A group is a column on the periodic table. The elements in a group react similar to the other elements in their group. Their are patterns in the physical properties of a group.

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An element key shows information about the element. It tells you as in the image says the name of the element, the atomic number, the atomic mass, the symbol and the state of matter.

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Mendeleev's table listed the table according to the elements' atomic mass. Instead, in the early 1900s, a scientist named Henry Moseley, developed the table by arranging the elements by their atomic number.

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The problem in Mendeleev's table was that some elements were out of place. The solution was the periodic table we use today.

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Predicting Properties of Undiscovered Elements

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Predicting Properties of Undiscovered Elements

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Mendeleev's table had large gaps. This was because he predicted that new elements were going to be discovered. He also predicted that the properties of the new elements were going to be similar to the elements that were right there.

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There are 100 elements, each one with its unique properties. A periodic table is a table arranged into rows and columns that shows the elements and their properties

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In the periodic table, Mendeleev noticed that there are properties that repeat patterns, like the melting and boiling point.

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A chemist and teacher Dimitri Mendeleev developed a table in 1869

He studied the physical properties of the elements

Mendeleev arranged the groups into rows of increasing atomic mass.

Elements with similar properties were in the same column