Question

If you eat metallic sodium or inhale chlorine gas, you stand a strong chance of dying. Let these two elements react with each other, however, and you can safely sprinkle the compound on your popcorn for better taste. What is going on?

Short answer

Sodium and chlorine react to form safe-to-eat sodium chloride (table salt).

Step-by-step solution

Understand the Properties of Elements

Metallic sodium and chlorine gas are both highly reactive elements. Sodium is a soft, highly reactive metal that can cause burns when exposed to moisture. Chlorine gas is a toxic, greenish-yellow gas that can damage the respiratory tract if inhaled.

Reaction of Sodium with Chlorine

When sodium (Na) and chlorine (Cl_2) are combined, they undergo a chemical reaction. Sodium donates one electron to form a sodium ion (\[\text{{Na}}^+\]) while chlorine gains this electron to form a chloride ion (\(\text{{Cl}}^-\)). This exchange of electrons forms an ionic bond.

Formation of Sodium Chloride

The ionic bond between sodium ions and chloride ions results in the formation of sodium chloride (\(\text{NaCl}\)). Sodium chloride is a stable compound that is non-toxic and safe for consumption.

Properties of Sodium Chloride

Unlike the individual elements, sodium chloride is an inert and safe compound commonly known as table salt. It is used widely in cooking and as a flavor enhancer, indicating that its chemical properties and effects differ significantly from its constituent elements.

Key concepts

Sodium Chloride

When sodium and chlorine come together, they create something wonderful: sodium chloride, or what you might know as table salt.
Sodium chloride is the compound formed when sodium (a metal) and chlorine (a gas) react chemically. This compound is stable, safe, and a common part of our diets. Unlike its reactive and potentially dangerous component elements, sodium chloride does not pose the same risks.
This transformation from harmful elements to safe compound exemplifies the intriguing world of chemistry, where interactions can drastically change a substance's properties.

• Stable and Safe: This compound is not reactive like its elements and is safe for everyday use.
• Widespread Use: Commonly used in cooking and food preservation, sodium chloride is a kitchen staple.

Ionic Bonds

An ionic bond forms when one atom transfers an electron to another atom, creating ions. This is precisely what happens with sodium and chlorine.
Sodium, which has one electron in its outer shell, eagerly donates this electron. Chlorine, which is looking to complete its outer shell, happily accepts this electron.
Here’s a closer look at this process:

• Electron Donor: Sodium becomes a positively charged ion (\(\text{Na}^+\)) after donating an electron.
• Electron Acceptor: Chlorine becomes a negatively charged ion (\(\text{Cl}^-\)) upon gaining an electron.

The result is a strong electrostatic attraction between the oppositely charged ions, holding them together in an ionic bond. This type of bond is responsible for the structure and stability of compounds like sodium chloride, making it possible for us to safely use substances that are toxic in their elemental forms.

Properties of Elements

Every element has distinct properties that define it. Sodium and chlorine are excellent examples of this.
Sodium is a soft metal, silver-white in color. It reacts vigorously with water, sometimes explosively, due to its eagerness to shed an electron.
Chlorine is a greenish-yellow gas, corrosive and toxic, especially dangerous when inhaled.
Despite these hazardous properties, when sodium and chlorine bond, they form sodium chloride—a completely new substance with completely different properties.

• Reactivity: Both sodium and chlorine are highly reactive and dangerous on their own.
• Transformation: The reaction of sodium and chlorine to form sodium chloride dramatically changes their properties.

Understanding elemental properties helps us comprehend how compounds form and behave in safe and beneficial ways.