How many valence electrons does Ra have?

Radium (Ra) is an element found in group 2 of the periodic table, which is also known as the alkaline earth metals. To determine the number of valence electrons in radium, we can look at its position in the periodic table and its electron configuration.

Understanding Valence Electrons

Valence electrons are the electrons located in the outermost shell of an atom. These electrons play a crucial role in chemical bonding and reactions. Elements in the same group of the periodic table typically have the same number of valence electrons, which is a key factor in their similar chemical properties.

Radium's Position in the Periodic Table

Radium is located in group 2 and period 7. Being in group 2 means that it has two valence electrons. This is characteristic of all alkaline earth metals, which include beryllium, magnesium, calcium, strontium, barium, and radium.

Electron Configuration of Radium

The electron configuration of radium can be written as follows:

• 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s²

From this configuration, you can see that the outermost shell (the seventh shell) contains two electrons in the 7s subshell. These two electrons are the valence electrons for radium.

Summary of Radium's Valence Electrons

To summarize, radium has two valence electrons. This characteristic is important for understanding how radium interacts with other elements and compounds, particularly in terms of its reactivity and the types of bonds it can form.

Real-World Implications

The presence of two valence electrons means that radium tends to lose these electrons easily during chemical reactions, allowing it to form positive ions (Ra²⁺). This property is significant in various applications, including its use in radiation therapy and as a source of radon gas in certain contexts.