Group 17 Elements: Halogens' Secrets Finally Revealed!

The Periodic Table, a cornerstone of chemistry, organizes elements based on their properties. Halogens, known for their high reactivity, occupy a specific column within this table. Understanding electron affinity, a fundamental property of atoms, helps explain the behavior of these elements. Therefore, knowing what are elements in group 17 called is essential to comprehending their place within the framework of modern chemistry and its applications in the realm of industrial applications, from disinfectants to pharmaceuticals.

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Unveiling the Mysteries: The Elements of Group 17

This article aims to comprehensively explain the elements belonging to Group 17 of the periodic table, commonly known as halogens, with a central focus on answering the question: What are elements in group 17 called? The article will cover their properties, reactions, applications, and safety precautions.

Introduction to Group 17: The Halogens

Group 17 of the periodic table houses a fascinating collection of elements. But what are elements in group 17 called? They are known as halogens. The term "halogen" comes from Greek roots meaning "salt-forming," aptly describing their tendency to react with metals to produce various salts.

Naming and Etymology

• The term "halogen" was coined in the 19th century to reflect their salt-forming nature.
• The individual names of the halogens are also derived from Greek or Latin roots, often alluding to their characteristic colors or properties.

Identifying the Halogens: A List of Members

This section provides a clear enumeration of the elements residing in Group 17.

1. Fluorine (F): A pale yellow gas.
2. Chlorine (Cl): A greenish-yellow gas.
3. Bromine (Br): A reddish-brown liquid.
4. Iodine (I): A dark purple solid.
5. Astatine (At): A radioactive element; very rare.
6. Tennessine (Ts): A synthetic, extremely radioactive element.

Properties of Halogens: A Deeper Dive

The halogens share several characteristic properties, largely due to their electronic configuration.

Physical Properties

• State of Matter: Halogens exist in all three states of matter at room temperature (gas, liquid, and solid).
• Color: They exhibit distinct colors, as noted in the list above, which deepen as you move down the group.
• Volatility: Their volatility decreases down the group; fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid that readily sublimes.

Chemical Properties

• High Electronegativity: Halogens are highly electronegative, meaning they strongly attract electrons. This is why they readily form negative ions (anions).
• Reactivity: They are highly reactive elements, eager to gain one electron to achieve a stable noble gas configuration. Fluorine is the most reactive halogen.
• Oxidizing Agents: Halogens are strong oxidizing agents, readily accepting electrons from other substances.

Table Summarizing Key Properties

Reactions of Halogens: Forming Bonds

Halogens participate in a wide range of chemical reactions. Their high reactivity stems from their strong desire to gain an electron.

Reaction with Metals

Halogens react vigorously with metals to form metal halides (salts). For example:

• 2Na (sodium) + Cl₂ (chlorine) → 2NaCl (sodium chloride – table salt)

Reaction with Nonmetals

Halogens also react with nonmetals, such as hydrogen:

• H₂ (hydrogen) + Cl₂ (chlorine) → 2HCl (hydrogen chloride)

Reactions with Each Other

Halogens can react with each other to form interhalogen compounds (e.g., ClF, BrF₃).

Applications of Halogens: From Disinfectants to Refrigerants

Halogens have numerous applications in various industries and everyday life.

Fluorine

• Used in toothpaste to prevent tooth decay (fluoride).
• Used in the production of Teflon (a non-stick coating).

Chlorine

• Used to disinfect drinking water and swimming pools.
• Used in the production of plastics like PVC.

Bromine

• Used in flame retardants.
• Used in the production of certain pharmaceuticals.

Iodine

• Used as an antiseptic for cuts and wounds.
• Used as a nutritional supplement (iodized salt).

Safety Precautions: Handling Halogens with Care

Due to their high reactivity, halogens can be hazardous.

Toxicity

• Halogens are generally toxic and can cause burns and respiratory problems.
• Fluorine is the most dangerous.

Handling

• Halogens should only be handled in well-ventilated areas.
• Appropriate personal protective equipment (PPE) should be worn, including gloves, goggles, and a lab coat.

Storage

• Halogens should be stored in tightly sealed containers away from incompatible materials.

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