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According to Le Chatelier's principle, changes in pressure only affect the position of equilibrium in gaseous reactions if there is a difference in the total number of moles of gas between the reactant and product sides of the balanced chemical equation. In the scenario described, there is "no change in volume in a gaseous reaction," which implies that the total number of moles of gaseous reactants is equal to the total number of moles of gaseous products. For example, H\(_2\)\(_{(g)}\) + I\(_2\)\(_{(g)}\) ⇌ 2HI\(_{(g)}\). When the number of moles of gas is the same on both sides, both the forward and backward reaction rates increase or decrease equally in response to a pressure change, so the equilibrium position remains unchanged.

Sodium chloride (\(\text{NaCl}\)) is a salt formed from the neutralization reaction of a strong acid (hydrochloric acid, \(\text{HCl}\)) and a strong base (sodium hydroxide, \(\text{NaOH}\)). When it dissolves in water, neither the sodium ions nor the chloride ions undergo significant hydrolysis (reaction with water). As a result, the concentrations of \(\text{H}^{+}\) and \(\text{OH}^{-}\) ions in the water remain essentially unchanged, and the solution maintains a neutral pH of approximately 7.

The spontaneity of a reaction is determined by the Gibbs free energy change (\(\Delta G\)), given by the equation:\(\Delta G=\Delta H-T\Delta S\)For a reaction to be spontaneous, \(\Delta G\) must be negative (\(\Delta G<0\)). For the given reaction: Entropy Change (\(\Delta S\)): The reaction involves the conversion of one mole of gas into one mole of solid and one mole of gas. The formation of a highly ordered solid from a less ordered gas results in a decrease in entropy, so \(\Delta S\) is negative (\(\Delta S<0\)).Enthalpy Change (\(\Delta H\)): Since the entropy change is negative, the term \(-T\Delta S\) is positive. For \(\Delta G\) to be negative (spontaneous), the \(\Delta H\) term must be sufficiently negative to overcome the positive \(-T\Delta S\) term. Therefore, the reaction must be exothermic, meaning \(\Delta H\) is negative (\(\Delta H<0\)). Therefore, for this specific reaction to be spontaneous, the enthalpy change (\(\Delta H\)) must be negative.

The reaction provided shows ethanol (\(\text{C}_{2}\text{H}_{5}\text{OH}\), an alcohol) reacting with ethanoic acid (\(\text{CH}_{3}\text{COOH}\), a carboxylic acid) to produce ethyl ethanoate (\(\text{CH}_{3}\text{COOC}_{2}\text{H}_{5}\), an ester) and water (\(\text{H}_{2}\text{O}\)). The formation of an ester and water from an alcohol and a carboxylic acid is defined as an esterification reaction. This is also a type of condensation reaction, where two molecules combine to form a larger one, eliminating a small molecule (water) in the process. A. condensation: While esterification is a type of condensation reaction, "esterification" is the specific name for the reaction forming an ester. B. fermentation: Fermentation is the process of breaking down organic molecules, such as glucose into ethanol and carbon dioxide, in the absence of oxygen, usually with microorganisms. It is not the process shown in the reaction. D. hydrolysis: Hydrolysis is the reverse reaction, where an ester breaks down into a carboxylic acid and an alcohol by reacting with water. The correct answer is option C - Esterification

To identify the specific acid and alcohol reactants, we can reverse this process by adding water back to the ester molecule: The part with the carbonyl group (\(\text{COO}\)) comes from the carboxylic acid. The \(\text{CH}_{3}\text{CH}_{2}\text{COO}\) part corresponds to propanoic acid (\(\text{CH}_{3}\text{CH}_{2}\text{COOH}\)).The alkyl group attached to the oxygen atom (\(\text{O}\)) comes from the alcohol. The \(\text{CH}_{2}\text{CH}_{3}\) group corresponds to ethanol (\(\text{CH}_{3}\text{CH}_{2}\text{OH}\)). Thus, the reaction that forms ethyl propanoate is between propanoic acid and ethanol. A. ethanol and ethanoic acid: These reactants would form ethyl ethanoate (\(\text{CH}_{3}\text{COOCH}_{2}\text{CH}_{3}\)), not ethyl propanoate. B. propanol and propanoic acid: These reactants would form propyl propanoate (\(\text{CH}_{3}\text{CH}_{2}\text{COOCH}_{2}\text{CH}_{2}\text{CH}_{3}\)), which has a three-carbon chain on both sides of the ester link, unlike the given structure. C. propanol and ethanoic acid: These reactants would form propyl ethanoate (\(\text{CH}_{3}\text{COOCH}_{2}\text{CH}_{2}\text{CH}_{3}\)), which also does not match the given structure. The correct option is D. propanoic acid and ethanol.

Stainless steel is widely used for making cutlery (knives, forks, spoons, and other utensils) due to its excellent properties. These properties include corrosion resistance (it doesn't rust easily), durability, hygiene, and non-reactive properties that make it safe for contact with food. B. permanent magnets: Permanent magnets are typically made from specific ferromagnetic alloys like Alnico, not stainless steel. Most common grades of stainless steel (austenitic) are non-magnetic. C. rock crushers: Rock crushers require extremely hard and wear-resistant materials to withstand the abrasive forces involved. While some specialized, high-strength stainless steel grades might be used in certain industrial contexts, the primary material for heavy-duty rock crushing components is usually manganese steel or other extremely tough alloys designed for high impact and abrasion, not standard stainless steel. D. bridges: While stainless steel can be used in certain components in bridge building for its corrosion resistance, especially in harsh environments, the primary structural material for most large bridges is typically structural steel (carbon steel) or concrete. The general use for "bridges" is less specific and less common than its use in cutlery manufacturing. The correct answer is option A - Cutlery

Basicity refers to the number of replaceable hydrogen ions (H\(^+\)) an acid molecule can furnish in a solution. The basicity of oxalic acid (C\(_2\)H\(_2\)O\(_4\)) is 2, meaning it's a dibasic acid because each molecule can donate two protons (H\(^+\)) when ionized in water, forming two replaceable hydrogen atoms and reacting with two moles of hydroxide ions, allowing it to form normal salts like K\(_2\)C\(_2\)O\(_4\).

The enzymatic conversion of glucose to ethanol is a biochemical process called fermentation, primarily catalyzed by the enzyme complex zymase, found in yeast, breaking down sugar into ethanol and carbon dioxide, crucial for brewing, baking, and biofuels. The overall chemical equation for the conversion of glucose to ethanol via fermentation is C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂, where one molecule of glucose (C₆H₁₂O₆) breaks down into two molecules of ethanol (C₂H₅OH) and two molecules of carbon dioxide (CO\(_2\)). Glucose polymerization links many glucose monomers (units) into long chains (polymers) like starch, cellulose, and glycogen, forming essential carbohydrates for energy storage (starch/glycogen) or structure (cellulose). The hydrogenation of glucose is a catalytic process that adds hydrogen to its carbonyl group, reducing it to a primary alcohol and converting the sugar into sorbitol, a widely used sugar alcohol. Saponification is the chemical process where fats or oils react with a strong alkali (like sodium or potassium hydroxide) to produce soap (a fatty acid salt) and glycerol.

Gold does not require complex extraction because it's a noble metal that is highly unreactive (inert), allowing it to be found in its pure, elemental (native) form in nature as nuggets or flakes, rather than locked in compounds, making options B and C correct, but C is the direct reason for not needing extraction from ore. Therefore, while being precious (A) and neutral (D, technically, as it's an element), the key reason it's found easily is its inert nature (B) and presence as a free element (C).

The Contact Process is the main industrial method for making concentrated sulphuric acid (H\(_2\)SO\(_4\)), involving three steps: burning sulphur to get sulphur dioxide (SO\(_2\)), catalytically oxidizing SO\(_2\) with oxygen to form sulphur trioxide (SO\(_3\)) using a vanadium(V) oxide catalyst, and then absorbing SO\(_3\) into concentrated sulphuric acid to create oleum, which is finally diluted to the desired strength. The Bosch process is primarily used for the industrial-scale production of hydrogen gas, (H\(_2\)). The Frasch process is used for producing sulphur. The Haber process (or Haber-Bosch process) is used to produce ammonia (NH\(_3\)).

Catalytic hydrogenation of benzene (C₆H₆) is a chemical process that requires high temperature, high pressure, and a catalyst (such as nickel or platinum). During this reaction, three molecules of hydrogen (H₂) are added across the three double bonds of the benzene ring, converting the aromatic compound into a saturated cyclic alkane, which is cyclohexane (C₆H₁₂).

Tristearin is a triglyceride, which is an ester of glycerol and three fatty acid molecules. Alkaline hydrolysis of fats and oils, a process called saponification, yields soap (the salt of the fatty acid) and glycerol. Glycerol, also known as propane-1,2,3-triol, is an alkanol with three hydroxyl (-OH) groups in its structure, making it a trihydric alkanol. A. dihydric alkanol is incorrect because a dihydric alkanol (e.g., ethane-1,2-diol or glycol) has only two hydroxyl groups, while glycerol produced from the reaction has three. B. tertiary alkanol and C. secondary alkanol are incorrect because they refer to the position and number of hydrogen atoms attached to the carbon atom bearing the hydroxyl group in monohydric alcohols. The product, glycerol, is a trihydric alkanol.

For a reaction to be feasible (spontaneous), the change in Gibbs free energy (\DeltaG) must be negative (\DeltaG<0). The Gibbs free energy is related to the enthalpy change (\DeltaH) and entropy change (\DeltaS) by the equation: \DeltaG = \DeltaH −T\DeltaS In the given reaction, 2SO\(_2\)\(_{(s)}\) + O\(_2\)\(_{(s)}\) ⇌ 2SO\(_3\), there are 3 moles of solid reactants forming 2 moles of solid products. A decrease in the number of moles of solid generally leads to a decrease in entropy, so \DeltaS would be negative. The formation of SO\(_3\) from SO\(_2\) and O\(_2\) is an exothermic reaction, meaning \DeltaH is negative. When \DeltaH is negative and \DeltaS is negative, the reaction is feasible at low temperatures. Based on the options provided: A. \DeltaH = +ve, \DeltaS = +ve; Feasible only at high temperatures. B. \Delta? = 0, \DeltaS= + ve ; Feasible at all temperatures as \DeltaG would be negative. C. \DeltaH = +ve , \DeltaS = −ve : This combination always results in a positive \DeltaG, so the reaction is never feasible in the forward direction as written. D. \DeltaS = 0: Feasible if \DeltaH is negative. The condition which makes any reaction not feasible is a positive \DeltaH and a negative \DeltaS. If both are positive, low T makes −T\DeltaS negative, so high T favours negative \DeltaG (spontaneous).

The production of sodium metal and chlorine gas from molten sodium chloride (NaCl) using electricity is an industrial process known as the Downs process. In this process, molten NaCl undergoes electrolysis in a specialized Downs cell, where the Na⁺ ions are reduced to liquid sodium at the cathode, and Cl⁻ ions are oxidized to chlorine gas at the anode. A. Browning process: There is no widely recognized industrial process by this name for sodium production. B. Chlor process: This likely refers to the chlor-alkali process, which is the electrolysis of aqueous sodium chloride (brine) to produce chlorine, hydrogen, and sodium hydroxide (NaOH), not pure sodium metal. D. Bosch process: The Bosch process (often related to the Haber-Bosch process for ammonia synthesis) is not involved in the production of sodium and chlorine from NaCl.

Chlorofluorocarbons (CFCs) were widely used as blowing agents for foams and packing materials due to their stability and non-toxicity. They help create bubbles or cavities in the foams, giving them their lightweight and insulating properties. B. tyre industry: CFCs were not used as blowing agents in the tyre industry; they were primarily associated with foam production and other applications. C. refrigerant: While CFCs (like Freon) were widely used as refrigerants, the question specifically asks about their application as a blowing agent. D. propellant: CFCs were also used as propellants in aerosol sprays, but the primary application for a blowing agent is in the foam industry. The correct answer is option A - foam industry.