Difference Between Radical and Valency

Thekey difference在激进和价值之间radical is a chemical species that has anunpaired electron,whereas valency is a chemical concept that describes the ability of a chemical element to combine with another chemical element。

A radical is a very reactive chemical species because it has an unpaired electron. Valency is the combining power of an element, especially as measured by the number ofhydrogen atomsit can displace or combine with.

内容

1.Overview and Key Difference
2.What is Radical
3.What is Valency
4.Side by Side Comparison – Radical vs Valency in Tabular Form
5.概括

What is Radical?

激进的化学物种unpaired electron. The unpaired electron is a最外层电子。这意味着；它位于原子的最外壳中。自由基可以是原子，分子或离子。由于不配对电子的存在是不稳定的，因此自由基是非常反应性的化学物种。因此，这些化学物种的寿命很短。

此外，激进分子可以以不同的方式产生。典型的方法是氧化还原反应。其他重要方法包括ionizing radiation, heat, electrical discharges, electrolysis, etc. These radicals are intermediates of many chemical reactions.

What is Valency?

Valency is the combining power of an element, especially as measured by the number of hydrogen atoms it can displace or combine with. It is a chemical concept that measures the reactivity of a chemical element. However, it can describe only the connectivity of atoms, but it does not describe the geometry of a compound.

We can determine the valency of a chemical element by observing the position of that element in the periodic table. The periodic table has all the chemical elements according to the number of electrons in the outermost shell of the atom. The number of electrons in the outermost shell determines the valency of the atom as well. For example, group 1 elements in the periodic table have one outermost electron. Therefore, they have one electron for the displacement or the combination with a hydrogen atom; thus, the valency is 1.

Furthermore, we can determine the valency using the chemical formula of a compound. Here, the basis of this method is the octet rule. According to theoctet rule, an atom tends to complete its outermost shell by either filling up the shell with electrons or by removing the extra electrons. For example, if we consider the compound NaCl, the valency of Na is 1 because it can remove one electron that it has in the outermost shell. Similarly, the valency of Cl is also 1 because it tends to gain one electron to complete its octet.

However, we should not be confused with the terms oxidation number and valency because oxidation number describes the charge that an atom can carry with it. For example, the valency of nitrogen is 3, but the oxidation number can vary from -3 to +5.

What is the Difference Between Radical and Valency?

The key difference between radical and valency is that radical is a chemical species that has an unpaired electron, whereas valency is a chemical concept that describes the ability of a chemical element to combine with another chemical element. In terms of electrons, the difference between radical and valency is that radical has one unpaired electron, while the valency of a chemical element describes the electrons in the outermost shell.

摘要 - 激进与价值

The key difference between radical and valency is that radical is a chemical species that has an unpaired electron, whereas valency is a chemical concept that describes the ability of a chemical element to combine with another chemical element.

Reference:

1. “Radical (Chemistry).”Wikipedia, Wikimedia Foundation, 25 June 2019,Available here。

Image Courtesy:

1. “Hydroxyl radical” By SmokeyJoe – Own work(CC BY-SA 4.0)viaCommons Wikimedia
2. “Periodic table vectorial” By Rubén Vera Koster – Own work(CC BY-SA 4.0)viaCommons Wikimedia