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export default {
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      return Response.redirect(`https://yourdomain.com`, 301);
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}; //for cloudflare deployment

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Bromine (Br) and Bromides

Bromine (atomic number 35) is the only non-metallic element that exists as a liquid at room temperature. It is a dense, volatile, red-brown fuming liquid with a strong, unpleasant odor. Bromine belongs to the halogen group (Group 17) and shows typical halogen reactivity — highly electronegative and a strong oxidizing agent.

Physical Properties (at 25 °C)

• Appearance: reddish-brown liquid
• Density: 3.10 g/cm³ (heavier than water)
• Melting point: −7.2 °C
• Boiling point: 58.8 °C
• Solubility in water: low (~33 g/L), but forms aqueous bromine (Br₂(aq))
• Characteristic color in different solvents:
  • Water → yellow-orange
  • Organic solvents (CCl₄, CHCl₃) → deep red-brown

Important Chemical Reactions of Bromine (Inorganic)

1. Reaction with metals (most vigorous with active metals)

$$ \ce{2Na + Br2 -> 2NaBr} $$

$$ \ce{Mg + Br2 -> MgBr2} $$

$$ \ce{2Al + 3Br2 -> 2AlBr3} \quad \text{(anhydrous condition, very exothermic)} $$

2. Reaction with hydrogen

$$ \ce{H2 + Br2 ⇌ 2HBr} \quad \Delta H = -103~\text{kJ/mol} \quad \text{(reversible, slower than Cl₂)} $$

Requires heating or UV light; equilibrium lies far to the right at low temperature.

3. Displacement reactions (bromine is less reactive than chlorine)

$$ \ce{Cl2 + 2NaBr -> 2NaCl + Br2} $$

$$ \ce{Br2 + 2I^- -> 2Br^- + I2} \quad \text{(brown → purple in organic layer)} $$

This is the basis for detecting bromide and iodide ions in qualitative analysis.

4. Reaction with water (partial hydrolysis)

$$ \ce{Br2 + H2O ⇌ HOBr + HBr} $$

The mixture is called "bromine water" and contains hypobromous acid (HOBr), which is responsible for its bleaching and oxidizing properties.

5. Preparation of bromine from bromide salts (industrial/lab)

$$ \ce{2NaBr + Cl2 -> 2NaCl + Br2} $$

$$ \ce{2Br^- + Cl2 -> Br2 + 2Cl^-} $$

Common Bromide Salts and Their Properties

Compound	Formula	Solubility in water	Remark / Use
Sodium bromide	NaBr	Very soluble	Source of Br⁻, sedative (historical)
Potassium bromide	KBr	Very soluble	Spectroscopy (IR windows), old anticonvulsant
Calcium bromide	CaBr₂	Very soluble	Oil drilling fluids (high density)
Silver bromide	AgBr	Insoluble	Light-sensitive — used in photography
Hydrogen bromide	HBr	Extremely soluble	Strong acid, source of Br⁻ in organic synth

Selected Organic Reactions Involving Bromine / Bromides

1. Electrophilic addition to alkenes (anti addition)

$$ \ce{CH2=CH2 + Br2 -> CH2Br-CH2Br} $$

$$ \ce{CH3-CH=CH-CH3 + Br2 ->[CCl4] CH3-CHBr-CHBr-CH3} \quad \text{(meso + racemic mixture)} $$

2. Allylic bromination (Wohl–Ziegler reaction using NBS)

$$ \ce{R-CH2-CH=CH2 + NBS ->[CCl4][\Delta or hv] R-CHBr-CH=CH2 + succinimide} $$

Highly selective for allylic position.

3. Aromatic bromination (electrophilic substitution)

$$ \ce{C6H6 + Br2 ->[FeBr3] C6H5Br + HBr} $$

Requires Lewis acid catalyst (FeBr₃, AlBr₃). Benzene bromination is slower than chlorination.

4. SN2 reaction with bromide as nucleophile

$$ \ce{CH3CH2Cl + Br^- ->[acetone] CH3CH2Br + Cl^-} $$

Bromide is a good nucleophile in polar aprotic solvents (Finkelstein-like reaction).

5. Hunsdiecker reaction (decarboxylative bromination)

$$ \ce{R-COOH ->[1. Ag2O][2. Br2] R-Br + CO2} $$

Useful for preparing alkyl bromides with one less carbon.

Summary – Reactivity Order of Halogens

F₂ > Cl₂ > Br₂ > I₂ (oxidizing power / reactivity)

I⁻ > Br⁻ > Cl⁻ > F⁻ (nucleophilicity in protic solvents)

Br⁻ ≈ I⁻ > Cl⁻ >> F⁻ (leaving group ability in SN1/SN2)

Bromine and bromide compounds therefore occupy a sweet spot in both inorganic and organic chemistry: reactive enough to participate in many transformations, yet selective enough to be synthetically useful.