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The atomic number (Z) is equal to the total number of electrons in a neutral atom. By summing the exponents in the electron configuration: 2+2+6+2+4 = 16 An atomic number of 16 identifies the element as Sulphur (S). Element Y belongs to group VI because it has six electrons in its outermost shell.

A tertiary alcohol (or alkanol) is one in which the hydroxyl (-OH) group is attached to a carbon atom that is directly bonded to three other carbon atoms. In the case of 2-methylpentan-2-ol: The parent chain is pentane (5 carbons), the hydroxyl group is on carbon-2, a methyl branch is also on carbon-2. Consequently, the second carbon atom is bonded to: Carbon-1 (from the main chain) Carbon-3 (from the main chain) The carbon of the methyl group. However, because this central carbon is bonded to three other carbons, it is a tertiary carbon, making the molecule a tertiary alcohol.

Sodium is a highly reactive metal positioned high in the reactivity series. Because it is more reactive than hydrogen, it cannot be obtained by the electrolysis of its aqueous solution (brine), as water would be reduced at the cathode instead. Commercially, sodium is produced through the Downs process, which involves the electrolysis of its fused (molten) salt, sodium chloride (NaCl).

The characteristic shine or lustre of a metal is primarily caused by the presence of free (delocalized) electrons on its surface. Light Interaction: When light strikes a metal, these mobile electrons absorb the light energy. Reflection: The electrons oscillate and immediately re-emit the energy as light, resulting in specular reflection that gives metals their shiny appearance. Visibility: Because metals are opaque, light cannot pass through them; it is instead reflected by this "sea of electrons" back to our eyes.

Breaking chemical bonds is an endothermic process because it requires energy to be absorbed from the surroundings to overcome the attractive forces between atoms. Bond Making (Energy Out): Forming new chemical bonds is an exothermic process because energy is released when atoms settle into a more stable, lower-energy state. Net Result: A reaction is classified as exothermic overall if the energy released during the formation of new bonds (products) is greater than the energy required to break the original bonds (reactants). This excess energy is released to the surroundings, typically as heat.

Silver (Ag) is located below hydrogen in the reactivity series. For a metal to release hydrogen gas when reacted with a dilute acid like HCl, it must be more reactive than hydrogen to displace it from the acid. Because silver is less reactive, it cannot displace hydrogen ions (H\(^+\)) to form hydrogen gas (H\(_2\)), and thus no reaction occurs.

In gaseous ion (one not bonded to any ligands) or an isolated transition metal atom, all five d-orbitals (d\(_{xy}\), d\(_{yz}\), d\(_{xz}\),...) possess the exact same energy level. In quantum chemistry, orbitals that share the same energy are formally defined as degenerate. This symmetry exists because there is no external electric or magnetic field (such as that from approaching ligands) to distinguish the orbitals' orientations relative to one another.

Beryllium oxide (BeO) is an amphoteric oxide because it can react with both acids and bases.

Charcoal is an amorphous allotrope of carbon known for its highly porous structure. Specifically, animal charcoal (bone char) or activated carbon is used in the sugar industry to remove colored impurities from raw sugar syrup through a process called adsorption. These impurities are physically trapped on the large surface area of the charcoal particles, resulting in the clear solution needed to produce white refined sugar.

In the periodic table, the group number (the vertical column) indicates the number of valence electrons for main group elements (Groups 1, 2, and 13–18). For example: Elements in Group 1 have 1 valence electron, elements in Group 2 have 2 valence electrons etc

Nucleons are the subatomic particles that reside within the atomic nucleus. Specifically, they are: (i)Protons: Positively charged particles that determine the atomic number of an element. (ii)Neutrons: Electrically neutral particles that contribute to the mass and stability of the nucleus.

The ion present in the solution is Iron(II) (Fe\(^{2+}\)). When aqueous sodium hydroxide (NaOH) is added to a solution containing iron(II) ions, a dirty green precipitate of iron(II) hydroxide, (Fe(OH)\(_2\)), forms. This precipitate is insoluble in excess sodium hydroxide.

The chemical formula C\(_2\)H\(_4\) represents ethene (also known as ethylene), which is the simplest alkene containing a double covalent bond between two carbon atoms.During addition polymerization, the double bond between the carbon atoms in the ethene monomers breaks under high pressure and temperature. These monomers link together in a long chain of repeating units to form polyethene (or polyethylene), a widely used plastic.

In the scientific method, a hypothesis is a tentative explanation or an educated guess that can be tested through experimentation. When a hypothesis is rigorously tested and supported by a significant amount of evidence within the limits of what is currently known, it is elevated to the status of a theory.

The empirical formula is defined as the chemical formula that represents the simplest whole-number ratio of the atoms of each element present in a compound. For this reason, it is also frequently referred to as the simplest formula.