Is Rubidium a Metal? (+ 4 Fascinating Facts to Know)

Yes, rubidium is a metal. It is a soft, silvery-white alkali metal that belongs to Group 1 of the periodic table. Like other metals, it has a metallic luster, is a good conductor of heat and electricity, and is malleable and ductile. ¹

Well, this was just a simple answer. But there are few more things to know about this topic which will make your concept super clear.

So let’s dive right into it.

Why is rubidium a metal?

Rubidium is a metal because it has properties that are characteristic of metals. Metals are typically shiny, malleable, ductile, and good conductors of heat and electricity, and rubidium exhibits all of these properties.

Rubidium is a soft, silvery-white metal that is highly reactive, which is also a common characteristic of metals. It has a low melting point of 39.3 °C (102.7 °F) and a boiling point of 688 °C (1270 °F). ²

It is also an alkali metal, meaning it belongs to Group 1 of the periodic table, along with lithium, sodium, potassium, cesium, and francium.

The electron configuration of rubidium is [Kr] 5s¹, which means it has one valence electron in its outermost shell, making it highly reactive. ³ This reactivity is due to its low ionization energy, which means that it can easily lose its outer electron to form a positively charged ion.

Overall, the physical and chemical properties of rubidium classify it as a metal.

Properties of rubidium that classify it as a metal

Rubidium is classified as a metal due to the following properties:

• Shiny: Rubidium has a metallic luster, meaning it is shiny when exposed to air or polished. This property is due to its ability to reflect light.
• Malleable: Rubidium is malleable, meaning it can be hammered or pressed into shapes without breaking. This is due to the ability of its metallic bonds to stretch and deform without breaking. ⁴
• Ductile: Rubidium is ductile, meaning it can be drawn into thin wires without breaking. This is due to the ability of its metallic bonds to stretch and deform without breaking.
• Good conductor of heat: Rubidium is a good conductor of heat, meaning it can transfer heat easily. This is due to its ability to transfer thermal energy through its electrons.
• Good conductor of electricity: Rubidium is a good conductor of electricity, meaning it can transfer electrical energy easily. This is due to its ability to transfer electrical energy through its electrons.
• Low melting point: Rubidium has a low melting point of 39.3 °C (102.7 °F), meaning it can be easily melted and formed into different shapes.
• Reactivity: Rubidium is highly reactive, meaning it readily forms compounds with other elements. This is due to its low ionization energy, which allows it to easily lose its outer electron and form a positive ion. ⁵

How is rubidium different from other metals?

Here are some ways in which rubidium differs from other metals:

1. Rubidium is the second most electropositive element after francium, meaning it has a strong tendency to donate its valence electron to form chemical bonds. ⁶
2. Rubidium is a very soft metal and can be easily cut with a knife. It is one of the softest metals known.
3. Rubidium is highly reactive and must be stored in an inert atmosphere or under oil to prevent it from reacting with air or water vapor. ⁷
4. Rubidium is relatively rare in the Earth’s crust, and it is the 16th most abundant element in the earth’s crust with a concentration of 78 ppm. ⁸
5. Rubidium is used in specialized applications, such as in atomic clocks and in research on Bose-Einstein condensates, which are a state of matter formed at extremely low temperatures. ^{9 10 11}
6. Rubidium has radioactive isotopes that can be used in medical treatments, such as for cancer.

Further reading

Is Strontium a Metal or Nonmetal?
Is Silver a Metal or Nonmetal?
Is Cadmium a Metal?
Is Tin a Metal or Nonmetal?
Is Iodine a Metal or Nonmetal? 

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11. Hyperphysics.phy-astr.gsu.edu http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/rubbec.html