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Carbon is typically used as the anode in the electrolysis of brine. Carbon is relatively inert and can withstand the corrosive conditions of the electrolysis process.

Ag\(^+\) + e\(^-\) → Ag If 96500 C deposited 108g of Ag ∴ 10 x 4830C will deposit Xg of Ag X = \(\frac{{108}\times{4830}\times{10}}{96500}\) X = 54.06g

Energy change = \DeltaH\(_{product}\) - \DeltaH\(_{reactants}\) Given: \DeltaH\(_{CO_2}\) = - 393, \DeltaH\(_{CO}\) = - 110.4 , \DeltaH\(_{O_2}\) = 0 (The standard enthalpy of formation for molecular oxygen (O\(_2\)) is zero because oxygen in its diatomic form (O\(_2\)) is the most stable form of oxygen under standard conditions). Energy change (\DeltaH) = \DeltaH\(_{CO_2}\) - (\DeltaH\(_{CO}\) + \DeltaH\(_{O_2}\)) = - 393 - ( - 110.4 + 0) = - 393 + 110.4 = -282.6 kJ

Entropy is a thermodynamic parameter that measures the disorder or randomness of a system. In general, gases with greater molecular weights have greater entropy. Thus, the entropy energies are in the order: HF 173.779 \pm 0.003 J K-1mol-1 HCl: 186.9 J K-1mol-1 HBr: 198.7 J K-1mol-1 HI: 206.6 J K-1mol-1 . Consequently, HI has the highest entropy value while HF has the least because the greater the molecular weights the greater the entropy value.

In the endothermic reaction, an increase in pressure will favour the side with the lesser value of number of moles of the gaseous specie while a decrease in pressure will favour the side with a higher value of number of moles of the gaseous specie. From the above equation, the product(on the RHS) has a higher value of number of moles of NO\(_2\) i.e 2 moles, when compared to the number of moles of N\(_2\)O\(_4\), on the LHS. i.e 1 mole of N\(_2\)O\(_4\), Therefore, a decrease in pressure will favour more product formation.

According to Boyle's law, an increase in pressure is inversely proportional to volume at constant temperature. This implies as volume increases, pressure will decrease and vice versa. However, as we consider all the reactions given in the options, the total number of moles of the reactants (LHS) is equal to the total number of moles of the product (RHS) for option A, pressure and invariably volume will have little or no effect on the equilibrium system.

Charcoal is an amorphous allotrope of carbon, meaning it's a form of carbon that exists in an irregular, non-crystalline structure. Wood charcoal has a porous structure that provides a large surface area for adsorption, allowing it to absorb coloured material from sugar . Animal charcoal is obtained from bones, blood, and horn through destructive distillation, it has good adsorptive power and can decolourize raw sugar when boiled together. Activated carbon plays a multifaceted role in sugar cane refining, removing impurities and colourants from sugar solutions. Therefore, Charcoal is the allotrope of carbon used in the decolourization of sugar.

Upward displacement is the method of collection of gases that are less dense than air, while Downward delivery is the method of collection of gases that are more dense than air. Among the given options, only option A, Chlorine is denser than air, hence it can be collected by downward delivery.

Water gas is produced when steam is passed over red-hot carbon. Water gas has the chemical formula as CO + H\(_2\) The chemical reaction for the production of water gas is C(s) + H\(_2\)O(g) → CO(g) + H\(_2\)(g).

Sulphur(IV) Oxide bleaches coloured substances through the process of reduction. It removes oxygen from coloured substances and makes them colourless, but this change is reversible as atmospheric oxygen can re-oxidize the colourless products, causing the colour to return. In order to get a permanent bleaching action, Chlorine is recommended. This is because chlorine reacts with water to produce nascent oxygen, which acts as an oxidizing agent and permanently oxidizes coloured substances.

Carbon is tetravalent because its 2s and 2p atomic orbitals hybridize to form four sp³ hybrid orbitals. Carbon has four valence electrons, so it can form a maximum of four bonds. When a carbon atom's 2s and 2p orbitals hybridize, they form four equivalent sp³ hybrid orbitals. Each sp³ orbital can form a sigma bond, resulting in a tetrahedral geometry. Carbon's tetravalency, meaning its ability to form four bonds, is explained by the concept of sp3 hybridization. This hybridization involves the mixing of one s orbital and three p orbitals to create four equivalent sp3 hybrid orbitals. This allows the carbon atom to form four single bonds, as seen in methane (CH\(_4\)).

Aluminum hydroxide is used in the dyeing industry as a mordant. A mordant is a substance that helps dyes stick to fabrics by forming a complex with the dye that attaches to the fabric. In dyeing, salt's primary function is to enhance dye absorption and fixation, while a mordant's role is to create a chemical bond between the dye and the fiber, improving colourfastness and potentially altering the final shade. Salts often act as a dyeing promoter, increasing dye exhaustion from the dye bath. Mordants, on the other hand, are typically metallic salts or other substances that form a stable complex with both the dye and the fiber, ensuring the color remains vibrant and stable.

The most common way to prepare an alloy is to melt metals together and then pour the mixture into a mold to solidify. This method is called melting and mixing. Alloys are created by combining two or more metallic elements, or sometimes a metal with a non-metal, in a solid solution, compound, or mixture. The process typically involves melting the base metal and then adding the alloying agents. Mixing is easier in the liquid state than in the solid state, so most alloys are made by melting the base metal. Electroplating primarily adds a thin coating of metal to a substrate, not creating a true alloy with the base material. It can be used to enhance surface properties like corrosion resistance or wear resistance, but not to create a new alloy with specific metallurgical properties throughout the material. While welding can join different metals, it's primarily used for joining existing pieces of metal, not for creating alloys from scratch. While some methods involve processing metal oxides to create alloys, melting and mixing the metals directly is generally more common and efficient for most alloy production.

Transition metals have variable oxidation states because their valence electrons are in the d-orbitals with similar energies, allowing them to be used for bond formation in multiple ways. Transition metals have partially filled d-orbitals in their outer electron shell.

Sodium metal is always kept under oil, typically kerosene, because it is a highly reactive metal that readily reacts with oxygen and moisture in the air, potentially causing a fire if exposed directly; by submerging it in oil, this contact is prevented and the metal remains stable. Also, sodium metal reacts vigorously with oxygen and carbon dioxide in air as it is a highly reactive metal that can catch fire and burn when exposed to air. It reacts vigorously with air, especially in the presence of moisture. Sodium is a highly reactive metal that can ignite spontaneously in air. Option D would have been also correct but option C is more detailed and all encompassing because in air, we have O\(_2\). CO\(_2\). as well as water vapour. Therefore, option C is the correct answer In summary, while sodium reacts vigorously with all three (oxygen and water), preventing the reaction with oxygen and moisture is the most important reason for storing it under oil because these reactions are more exothermic and potentially dangerous.