Group 3

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Outline

• In this PowerPoint we will go over:• Alkali Metals• Alkali Earth Metals• How Alkali Metals and Alkali Earth Metals

compare and contrast

Alkali Metals

• Alkali Metals have closer characteristics than any other group

• Alkali Metals are soft and are silvery in color• Alkali Metals are reactive• No Alkali Metals are found in nature• All Alkali Metals have one electron in their

outer shell

Lithium

• Discovered in 1817 by Arfvedson• Not found in nature• Reacts violently with water• Lithium is corrosive and requires special

handling• Used in special glasses and ceramics

Sodium

• First isolated in 1807 by Davy• There is a lot of sodium in the Sun and stars• Sodium is the fourth most abundant element

in nature and the most abundant Alkali Metal on Earth

• Reactive with water

Potassium

• Discovered in 1807 by Davy• Insoluble• Used in fertilizers• One of the most reactive metals• Soft and easy to cut

Rubidium

• Discovered in 1861 by Bunsen and Kirchoff• Can be liquid at room temperature• Ignites spontaneously in air• Reacts violently in water

Cesium

• Discovered in 1860 by Bunsen and Kirchoff• Silvery-white color• Soft• Ductile• Reacts explosively with cold water• Melts at room temperature

Francium

• Discovered in 1939 by Mlle• Heaviest Alkali Metal• Most unstable of the first 101 elements• No weighable quantity of the element has

been prepared or isolated

Alkali Earth Metals

• All Alkali Earth Metals have two electrons in the outer shell

• All Alkali Earth Metals are not found in nature• All are silvery in color• All are softer than other metals but are not as

soft as Alkali Metals

Beryllium

• Discovered in 1798 by Vauquelin• First isolated in 1828 by Wohler and Bussy• Steel gray color• Lightest of all metals• Used in high-speed aircraft, missiles,

spacecraft, and communication satellites

Magnesium

• Eighth most abundant element • Silvery-white in color• Flammable• One-third lighter than aluminum• Used in flash photography and flares

Calcium

• Discovered in 1808• Fifth most abundant element on Earth• Found in leaves, bones, teeth, and shells• Silvery color• Harder than the other Alkali Earth Metals• Reacts with water

Strontium

• First isolated in 1808 by Davy• Silvery color• Soft• Used in refining zinc• Used to make fireworks red

Barium

• Discovered in 1808 by Davy• Silvery-white color• Decomposes in water or alcohol• Used in making rubber• Used in peroxide, chloride, sulfate, carbonate,

nitrate and chlorate

Radium

• Discovered in 1898 by Marie Curie• Present in all uranium minerals• White color• In its pure form, it blackens on exposure to air• Glows in the dark• Used in glow-in-the-dark paints

Compare

• Both Alkali and Alkali Metals are reactive, are silvery in color, are soft, and are not found in nature.

Contrast

• Alkali Metals have one electron in their outer shells while Alkali Earth Metals have two.

• Alkali Metals have low melting points in comparison to Alkali Earth Metals which have high melting points.

Summary

• In conclusion, Alkali and Alkali Earth Metals are very similar. Their difference with each other are minute but their differences with the other elements are great.