Halides: Metals, Anions, Haloalkanes and Haloarenes

Halides are the anion forms of halogen atoms, which are found in Periodic Table Group 7. Fluoride, chloride, and bromine are common halides found in natural water sources. Due to its great solubility in water, halides can be found in natural water sources such as rivers, lakes, and streams. Natural bedrock in running water and industrial discharge are both sources of halides. Increased chloride levels in metropolitan areas, for example, are almost entirely due to runoff from road deicing.

Key Terms: Halide ions, Halogen, atoms, metal halides, organic chemistry, Periodic Table, Fluoride, chloride, bromine, Water

---

Halides Definition

[Click Here for Sample Questions]

Halides are two-part binary compounds in which one part is an element and the other is a halogen atom. When compared to the halogens that form astatine, bromide, fluoride, and chloride, a radical is less electronegative. Halides make up the majority of the salts. Silver nitrate solution is used to test various halide compounds. Kl, KBr, and KCl are a few examples.

Precipitation is created when halogen combines with silver nitrate solution, and the colour varies based on the type of halides. Silver Fluoride with no precipitate is one of them, Precipitate of silver bromide with a pale yellow colour, Green precipitate of silver iodide, White precipitate of silver chloride.

The halide ion is a Halogen atom that has a negative charge. The halide anion is found in halide minerals. Two notable halide minerals are fluorite and halite. The principal source of hydrogen fluoride is fluorite. The mineral halite is a major source of sodium chloride. Bischofite is a key magnesium source. There is a presence of the halides in the marine evaporite deposits. Iodide, bromide, chloride, and fluoride are some of the halide anions.

Read More:- 

---

Halide Anions

[Click Here for Sample Questions]

Here is information about some of the halide anions.

1. Fluoride 

Fluoride is attracted to soil particles and can be dissolved in running water sources from soil samples that are nearby. Aquatic animals can be exposed directly to fluoride in natural water bodies, while terrestrial animals are also at danger from consuming fluoride-rich flora. Fluoride levels beyond a certain threshold are toxic to all species, resulting in stunted growth, bone disintegration, animal birth abnormalities, and reduced agricultural yields. The maximum allowable fluoride concentration in drinking water has been set at 2 parts per million (ppm) by the Environmental Protection Agency (EPA).

2. Inorganic Chloride

They contain salts, such as sodium chloride (table salt), and chlorinated tap water are both sources of chloride in natural streams. Drainage, precipitation, runoff, soil and clay sources, pollution, and garbage disposal are all potential causes. When these ions come into contact with natural water, they can and will react with naturally occurring molecules to generate chloroform and other carcinogens. It also contributes to the corrosion of many metals, including man-made structures like dams, due to its strong reactivity. The EPA's limit for chloride in drinking water is 250 parts per million.

3. Bromides 

They are found in both mining and natural water sources as inorganic salts. Increased levels can be caused by industrial dumping and runoff. Flatworms, snails, shrimp, and minnows are among the aquatic creatures that can be killed by high bromide concentrations. Bromide can be absorbed by plants as well, resulting in reduced growth and poor germination.

Metal Halides

Metal halides are mixtures of metals and halogens. Some of them are covalently bonded, whereas others are ionic. Metal ions that are covalently linked can create polymeric structures. When all halogens react with metal, metal halides form. It's stated out in the equation below.

2M + nX₂ → 2MXn

---

Haloalkanes and Haloarenes

[Click Here for Sample Questions]

The following are the classifications for haloalkanes and haloarenes:

On the basis of the number of halogen atoms: Depending on whether they include one, two, or more halogen atoms in their structures, these can be classed as mono, di, or polyhalogen (tri-, tetra-, etc.) compounds.

For examples: C₂H₅X(Mono Haloalkane), C₆H₅X(Mono Haloarene)

As stated below, mono halo compounds can be further divided on the basis of the hybridization of the carbon atom to which the halogen is bound.

Compounds Containing sp3 C—X Bond (X= F, Cl, Br, I)

1. Alkyl halides or haloalkanes (R—X): The halogen atom is bound to an alkyl group in alkyl halides (R). CnH₂n+1X represents a homologous series of them. According to the type of carbon to which halogen is linked, they are classed as primary, secondary, or tertiary.

Alkyl halides or haloalkanes

2. Allylic halides: These are compounds in which the halogen atom is attached to an allylic carbon atom that is sp3 hybridised close to the carbon-carbon double bond (C=C).

Allylic halides

100. Benzylic halides: The halogen atom is attached to an sp3-hybridised carbon atom adjacent to an aromatic ring in these molecules.

Benzylic halides

Compounds Containing sp² C—X Bond

1. Vinylic halides: The halogen atom is bonded to a sp2-hybridised carbon atom of a carbon-carbon double bond (C = C) in these compounds.

Vinylic halides

• Aryl halides: The halogen atom is bonded to the sp2 -hybridised carbon atom of an aromatic ring in these compounds.

Aryl halides

---

Uses of Halides

[Click Here for Sample Questions]

1. The solder paste contains halides. In synthetic organic chemistry, halogens are integrated into organohalides compounds.
2. It's a common component in high-intensity discharge metal halide lamp.
3. In a rainy climate or a greenhouse, they are employed as a supplement to supply sunshine.
4. In the papers and phosphoric films, silver halides are used.

---

Things to Remember

• Halides are the anion forms of halogen atoms, which are found in Periodic Table Group 7.
• Halides are two-part binary compounds in which one part is an element and the other is a halogen atom.
• Halides make up the majority of the salts. Silver nitrate solution is used to test various halide compounds. Kl, KBr, and KCl are a few examples.
• The halide ion is a Halogen atom that has a negative charge. The halide anion is found in halide minerals.
• Metal halides are mixtures of metals and halogens. Some of them are covalently bonded, whereas others are ionic.

Read More:-