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Relative molecular mass of CuSO\(_4\) = 64 + 32 + (16 x 4) = 160 The number of moles of CuSO\(_4\) = \(\frac{mass}{Molar mass}\) = \(\frac{20}{160}\) n = 0.125 mole 100g of water dissolved 0.125mole of CuSO\(_4\) 100g of water will dissolve \(\frac{0.125}{100}\times{1000}\) Solubility = 1.25 moldm\(^{-3}\) Alternatively, Solubility = Number of moles of solute x \(\frac{1000}{Volume of solvent}\) But Number of moles of solute = \(\frac{mass}{molar mass}\) = \(\frac{20}{160}\) = 0.125 moles Solubility = Number of moles of solute x \(\frac{1000}{Volume of solvent}\) Solubility = 0.125 x \(\frac{1000}{100}\) = 1.25 moldm\(^{-3}\)

Calcium sulphate is only slightly soluble in water, meaning that only a small amount of it will dissolve, and the rest will remain as a solid. Calcium sulfate in water forms a precipitate, not a suspension. While calcium sulfate is only slightly soluble in water, it does not form a true suspension where particles are suspended in the liquid. Instead, it generally forms a precipitate, which is a solid that separates from the solution and settles at the bottom. When calcium tetraoxosulphate(VI) dissolves sparingly in water, a precipitate is formed. Colloids and precipitates are both related to the separation of substances in a mixture, but they differ in particle size and the process that leads to their formation. Colloids are mixtures where particles are dispersed throughout another substance, but don't settle out quickly. Precipitates, on the other hand, are solid substances that form and separate from a solution during a chemical reaction.

A normal salt is formed when a metal or a group of elements behaving like a metal completely replaces replaceable hydrogen atoms in an acid molecule. Na\(_2\)CO\(_3\) (sodium carbonate), also known as washing soda or soda ash, is a type of normal salt. It's formed from a strong base (sodium hydroxide) and a weak acid (carbonic acid), making it a basic salt.

First, write a balanced equation for the chemical reaction: 2NaOH + H\(_2\)SO\(_4\) → Na\(_2\)SO\(_4\) + 2H\(_2\)O From the balanced equation, N\(_A\) = 1 ; N\(_B\) = 2 C\(_A\) = 0.5 moldm\(^{-3}\) ; V\(_A\) = ? ; C\(_B\) = 0.1 moldm\(^{-3}\) ; V\(_B\) = 20 cm\(^3\) Using the formula, \(\frac{{C_A}{V_A}}{{C_B}{V_B}}\) = \(\frac{N_A}{N_B}\) V\(_A\) = \(\frac{{C_B}{V_B}{N_A}}{{C_A}{N_B}}\) = \(\frac{{0.1}\times{20}\times{1}}{{0.5}\times{2}}\) V\(_A\) = 2.0 cm\(^3\)

The Oxidation state of H= +1 , O = - 2 , Cl = ? HClO\(_4\) = 0 +1 + Cl + (- 2 x 4) = 0 Cl = +8 - 1 Cl = + 7

A substance is reduced when it gains electrons or loses oxygen.i,e it undergoes reduction. while a substance is oxidized, when it loses electrons, gains oxygen, or has hydrogen removed. Therefore, Zn is reduced because it lost oxygen.

SO\(_2\) can act as both an oxidizing and reducing agent because it has multiple valencies, with the oxidation state of sulphur ranging from -2 to +6. It can oxidize hydrogen sulphide to sulphur, and carbon monoxide to carbon dioxide. It can lose electrons to other compounds, reducing itself to a lower valency state. For example, SO\(_2\) can reduce ferric to ferrous salts, and acidified potassium iodate to iodine. Therefore, sulphur dioxide, SO\(_2\) can act as both an oxidizing and reducing agent.

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.