Explanation

In the complex  [ 𝐹 𝑒 ( 𝑁 𝐻 3 ) 6 ] ^2 + , iron (Fe) is in the +2 oxidation state, meaning it has a  𝑑6 electron configuration.

Ammonia (NH₃) is considered a strong field ligand under Crystal Field Theory (CFT), causing the electrons in the 𝑑-orbitals to pair up due to the large splitting of the 

𝑑-orbitals.

In a strong field environment, the electrons occupy the lower energy  𝑡2𝑔 orbitals first, and all six electrons pair up, leaving no unpaired electrons.

Therefore, the number of unpaired electrons is 0.

Explanation

Ferromagnetic materials are those that can be magnetized and retain their magnetization even after the external magnetic field is removed.

These materials have a high magnetic permeability and strong interactions between magnetic moments, which align in the same direction.

Explanation

In the complex  [Ni(CN) 4] ^2−, nickel is in the +2 oxidation state and is surrounded by four cyanide (CN⁻) ligands.

According to Crystal Field Theory and based on the strong field nature of cyanide ligands, the complex adopts a square planar geometry.

Explanation

This is done through an electrophilic attack on the aromatic ring with the help of a carbonation.

The Friedel-Crafts alkylation reaction is a method of generating alkylbenzenes by using alkyl halides as reactants.

The Friedel-Crafts alkylation reaction of benzene is illustrated below.

Explanation

Alpha rays, or alpha particles, are the least penetrating form of radiation.

They consist of two protons and two neutrons.

Making them relatively large and heavy compared to beta and gamma rays.

Explanation

According to Valence Shell Electron Pair Repulsion (VSEPR) theory, XeF₄ (xenon tetrafluoride) has a square planar geometry.

Xenon in XeF₄ has six electron pairs around it: four bonding pairs and two lone pairs.

Explanation

The Tyndall effect is the scattering of light by particles in a colloid or in very fine suspensions.

When light passes through a colloidal solution, the dispersed particles scatter the light in different directions, making the path of the light visible.

Explanation

Osmium is the densest naturally occurring element, with a density of approximately 22.59 g/cm³.

This makes it the highest density transition element, far exceeding the densities of elements like mercury and zinc.

Explanation

Carbon dioxide (CO₂) is the gas commonly used in carbonated beverages.

It dissolves in the liquid under pressure, creating the fizzy bubbles that are characteristic of drinks like:

• soda
• sparkling water
• beer
  

Explanation

Sodium hypochlorite (NaClO), usually as a 3–6% solution in water

It is usually called "liquid bleach" or just "bleach"

Sodium hypochlorite acts as a powerful disinfectant and stain remover, making it effective for various cleaning and sanitizing purposes.