Question

If a nitrogen molecule, \(\mathrm{N}_{2}\), were to react with a reactive metal such as potassium, what charge would the resulting nitride ions have? How many electrons would be gained by each nitrogen atom? How many electrons would be gained by each \(\mathrm{N}_{2}\) molecule?

Short answer

In the reaction between nitrogen gas and a reactive metal like potassium, the resulting nitride ion has a charge of -3. Each nitrogen atom in the ion gains 3 electrons, and each \(\mathrm{N}_{2}\) molecule gains a total of 6 electrons.

Step-by-step solution

Identify the charge of nitride ions

First, we need to find the oxidation state of nitrogen in a nitride ion. Nitrogen is in group 15 (or 5A) of the periodic table, which means it has 5 valence electrons. To reach a stable electron configuration, nitrogen will gain 3 electrons to complete its octet. Therefore, the charge of the nitride ion (\(\mathrm{N}^{3-}\)) will be -3.

Determine the number of electrons gained by each nitrogen atom

Since each nitrogen atom gains 3 electrons to form the nitride ion, we can conclude that each nitrogen atom gains 3 electrons in this reaction.

Determine the number of electrons gained by each nitrogen molecule

A nitrogen molecule (\(\mathrm{N}_{2}\)) consists of two nitrogen atoms. As each nitrogen atom gains 3 electrons, the entire molecule will gain a total of 6 electrons. So, in this reaction: 1. The charge of a nitride ion is -3. 2. Each nitrogen atom gains 3 electrons. 3. Each \(\mathrm{N}_{2}\) molecule gains 6 electrons.

Key concepts

Nitride Ion

When nitrogen reacts with a highly reactive metal like potassium, it forms an ion known as the nitride ion. This occurs because nitrogen aims to achieve an electron configuration similar to that of noble gases, which are stable and non-reactive. In order to do this, nitrogen must gain electrons. Typically found in group 15 of the periodic table, nitrogen has a tendency to gain three electrons, resulting in the formation of the nitride ion with the chemical symbol \(\mathrm{N}^{3-}\). The "+3" represents the charge on the ion due to the addition of three extra electrons. This process is essential for understanding how nitrogen behaves in chemical reactions, particularly with metals.

• The nitride ion has a charge of -3.
• Formed when nitrogen gains 3 electrons.
• Symbolized as \(\mathrm{N}^{3-}\).

Understanding the formation of nitride ions is crucial in chemistry because it helps explain how ionic compounds form and the role of electron transfer in these reactions.

Oxidation State

The oxidation state is crucial for understanding chemical reactions, as it indicates how many electrons an atom gains, loses, or shares during a reaction. In the scenario where nitrogen forms a nitride ion, it is key to know its oxidation state. In its elemental form, nitrogen exists as \(\mathrm{N}_{2}\) and has an oxidation state of 0. However, when it gains electrons to form a nitride ion, the oxidation state of each nitrogen atom changes to -3.

• In neutral molecules, the oxidation state of an element is 0.
• Nitrogen shifts from 0 to -3 when it forms a nitride ion.

Understanding oxidation states allows for predictions about electron transfer during reactions, crucial for forming compounds.

Valence Electrons

Valence electrons play a vital role in chemical reactions and bonding. They are the outermost electrons of an atom and determine how it interacts with other elements. For nitrogen, which belongs to group 15 of the periodic table, there are 5 valence electrons. These electrons are key to how nitrogen achieves stability through chemical bonding. In the reaction forming nitride ions, nitrogen "wants" a full outer shell to achieve the noble gas configuration of 8 valence electrons, known as an octet. Each nitrogen atom does this by gaining 3 additional electrons. Hence, each nitrogen atom completes its octet and becomes part of a stable nitride ion.

• Nitrogen has 5 valence electrons naturally.
• Needs to gain 3 more for a full octet.
• Valence electrons determine molecular interactions and reactions.

Understanding valence electrons helps explain the nature of bonds formed during reactions and ensures a full comprehension of chemical stability.