Fluorine Valency Calculation

This solution explains how to determine the valency of Fluorine, given its electron configuration in the outermost shell.

Understanding Valency

The valency of an element is a measure of its combining power with other atoms. It's typically defined by the number of electrons an atom needs to gain, lose, or share to achieve a stable electron configuration. For most elements, this stable configuration involves having 8 electrons in their outermost electron shell, known as the octet rule.

Fluorine's Electron Structure

The question states that Fluorine has 7 electrons in its outermost shell. Fluorine's atomic number is 9, so its full electron configuration is 2 electrons in the first shell and 7 electrons in the second (outermost) shell.

How Fluorine Achieves Stability

Fluorine wants to achieve a stable configuration, which means having 8 electrons in its outermost shell.

• Fluorine currently has 7 electrons in its outermost shell.
• To reach 8 electrons, Fluorine needs to gain just 1 more electron.
• Gaining 1 electron is energetically more favorable than losing the 7 electrons it already has.

Therefore, Fluorine's combining capacity, or valency, is 1.

Analyzing the Options

Let's look at why the other options are not the best explanation:

• Option 1: 8, because it follows the octet rule
  This option confuses the target state (8 electrons) with the valency itself. Valency is how an atom achieves that state.
• Option 2: 7, because it has 7 electrons
  This is the number of valence electrons, not the valency. Valency considers the ease of achieving a stable octet.
• Option 3: 0, because it is a non-metal
  Valency isn't determined solely by whether an element is a non-metal. Many non-metals have non-zero valencies.
• Option 4: 1, because it gains 1 electron to complete an octet
  This accurately describes Fluorine's situation. It needs one electron to complete its octet, making its valency 1.

Conclusion on Fluorine's Valency

Based on its electron configuration of 7 electrons in the outermost shell, Fluorine needs to gain 1 electron to achieve a stable octet. Hence, its valency is 1.