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Fructose is a monosaccharide with the molecular formula C\(_6\)H\(_{12}\)O\(_6\). When represented by the general formula C\(_x\)(H2O)\(_y\), it can be written as C\(_6\)(H\(_2\)O)\(_6\). Therefore, the value for "X" (the number of carbon atoms) is 6. A. 3 is incorrect because a 3-carbon sugar (triose) like glyceraldehyde has the formula C\(_3\)H\(_6\)O\(_3\), which is not fructose. B. 12 is incorrect because 12 carbons indicates a disaccharide (like sucrose,C\(_{12}\)H\(_{22}\)O\(_{11}\)) or a polysaccharide, not a single fructose molecule. C. 5 is incorrect because a 5-carbon sugar (pentose) like ribose has the formula C\(_5\)H\(_{10}\)O\(_5\), which is not fructose. The correct answer is option D.

The phenomenon where particles from a gold bar migrate into a silver bar (and vice versa) when tied together for years is due to diffusion in solids. Diffusion is the process by which particles move from a region of higher concentration to a region of lower concentration, resulting in an even distribution. A. Brownian movement: This is the random motion of microscopic particles suspended in a fluid (liquid or gas), not the slow intermingling of atoms within solid metal bars. C. Displacement: This term generally refers to a change in position or the replacement of one element by another in a chemical reaction. It does not describe the physical process of gradual intermingling of atoms in the context of the question. D. Osmosis: This is a special case of diffusion that involves the movement of solvent molecules through a selectively permeable membrane. It is a process specific to fluids and membranes and does not apply to solid metals. :. The correct answer is Diffusion - option B

The correct options should be either option A. silver (or D. copper) as both metals can be found in the free state in nature. However, metals found in their free state in nature are typically the least reactive metals, often called noble metals, which do not readily combine with oxygen, water, or other elements in the atmosphere to form compounds. Based on this, we should go for option A since Silver is less reactive when compared to copper. B. Zinc: is a moderately reactive metal. It readily reacts with other elements and is found in nature as compounds like zinc sulphide (zinc blende). It is never found in a free state in large amounts. C. Iron: is more reactive than zinc and copper. It easily oxidizes (rusts) in the presence of air and moisture, so it is almost exclusively found in nature as iron oxides (ores like haematite and magnetite).

Propanol, CH\(_3\)CH\(_2\)CH\(_2\)OH has the highest boiling point among ethanol,(CH\(_3\)CH\(_2\)OH) propanol,(CH\(_3\)CH\(_2\)CH\(_2\)OH) hexane,(CH\(_3\)CH\(_2\)CH\(_2\)CH\(_2\)CH\(_2\)CH\(_3\) )and chloropropane, (CH\(_3\)CH\(_2\)CH\(_2\)Cl ) because its longer carbon chain and ability to hydrogen bond (like ethanol) create stronger intermolecular forces, requiring more energy to vaporize, with propanol (around 97^\circC) significantly beating ethanol (~78^\circC), hexane (~69^\circC), and chloropropane (similar to hexane/slightly higher due to polarity but less H-bonding than alcohols).

The correct inference from the graph is that solubility of Y increases steadily as temperature increases- option D. A. the solubility of X and Y is the same at all temperature: Incorrect. The lines for X and Y cross at a single temperature (~50^\circC), but at all other temperatures, their solubilities are different (e.g., Y is more soluble below ~50^\circC, X is more soluble above ~50^\circC). B. the solubility of X, Y and Z is temperature dependent: Incorrect. The line for Z is horizontal, indicating that its solubility is constant and does not change with temperature. C. solubility of Z increases as temperature increases: Incorrect. The horizontal line for Z shows that its solubility remains the same as the temperature increases. However, in option D, the solubility of Y increases steadily as temperature increases. This statement is Correct. Following the line for Y from left to right (increasing temperature), the line moves upwards, indicating a steady increase in solubility.

Hydrogen chloride (HCl) is the gas commonly used in the fountain experiment because of its exceptionally high solubility in water. When a small amount of water is introduced into a flask filled with HCl gas, the gas dissolves rapidly, creating a partial vacuum. B. hydrogen sulphide (H\(_2\)S) is not typically used for the fountain experiment. While it has some solubility, it is not as highly soluble as HCl or NH\(_3\), which are necessary for the dramatic effect of the fountain. It is also a toxic gas with a foul odor. C. dinitrogen(I) oxide (nitrous oxide, N\(_2\)O) and D. nitrogen(II) oxide (nitric oxide, NO) are gases with low solubility in water compared to HCl, and would not produce the significant pressure drop required for a successful fountain experiment. Therefore, the correct answer is option A.

The statement in option B is false because hard water can be supplied in lead pipes. The high mineral content in hard water (specifically calcium carbonate) forms an insoluble protective layer of scale on the inside of the pipes. This coating prevents the poisonous lead from dissolving and leaching into the water. It is soft water that can cause lead poisoning when supplied in lead pipes. A. Helps animals to build strong teeth is a correct statement. The dissolved calcium in hard water contributes to strong teeth and bones in animals and humans. C. Tastes better than soft water is generally considered a correct statement. The minerals present in hard water give it a distinct, often preferred, "full-bodied" or "mineral" taste compared to soft water. D. Helps animals to build strong bones is a correct statement, for the same reason as option A. Hard water is a natural source of essential minerals like calcium, which are vital for maintaining bone density and overall skeletal health. The correct answer is option B.

Firstly, determine the empirical formula. Molecular formula for the compound : C\(_6\)H\(_{12}\)O\(_6\) To find the empirical formula, the subscripts of each element must be divided by their greatest common divisor, which is 6. C\(_6\)H\(_{12}\)O\(_6\) → CH\(_2\)O Empirical formula : CH\(_2\)O Now, we can calculate the empirical mass of CH\(_2\)O = 12 + (1 x 2) + 16 = 30. :. The correct answer is option D

The process by which microorganisms (bacteria and fungi) break down complex organic nitrogen compounds in dead plants, animals, and waste materials is called ammonification. This process releases simpler inorganic forms, primarily ammonia (NH\(_3\)). In the soil, this ammonia reacts with water to form ammonium ions. B. trioxonitrate(V) is formed in a later stage of the nitrogen cycle called nitrification, where nitrifying bacteria convert the initial ammonia/ammonium into nitrites and then nitrates. C. ammonium salts are formed in the soil after ammonia is produced and dissolves in water, forming ammonium ions which are a component of the salts. However, the initial conversion of the organic material itself yields ammonia. D. dioxonitrate(III) is an intermediate compound in the nitrification process, produced when ammonia is converted by bacteria like Nitrosomonas. It is then further converted to trioxonitrate(V) by Nitrobacter. The correct answer is ammonia - option A

The IUPAC name for the compound CH\(_3\)C ≡ CHCH(CH\(_3\))\(_2\) is 4-methylpent-2-yne. First: Name the longest Carbon atom chain, with reference to the shorter route of the position of the triple bond ≡ i.e pent-2-yne (5 Carbon atom with ≡ on C-2) Secondly: name the substituent functional group. i.e the CH\(_3\) - methyl on C-4 ( 4- methyl) Thirdly: Combine second and first steps together. i.e 4-methyl and pent-2-yne. IUPAC Nomenclature of the compound above is 4-methylpent-2-yne - option B

Potassium chlorate (KClO\(_3\)) itself is not explosive under normal laboratory heating conditions (especially when mixed with a catalyst, which lowers the decomposition temperature). However, it is a very strong oxidizing agent. If the potassium chlorate comes into contact with easily oxidizable substances (carbonaceous materials like dust, rubber tubing, or grease) during the preparation, the mixture can become highly sensitive and explosive. This high risk of forming an explosive mixture is the primary reason why this method is usually not recommended in modern laboratories, favoring safer alternatives like the decomposition of hydrogen peroxide (H\(_2\)O\(_2\)). The correct option is A - it forms explosive mixture with carbonaceous materials.

Magnesium (Mg) is a reducing agent because it is oxidized during the reaction. Since a substance that is oxidized (loses electrons) is the reducing agent, while the substance that is reduced (gains electrons) is the oxidizing agent. In this specific reaction, the oxidation state of magnesium changes from 0 (in Mg(s)) to +2 (in MgCl₂(aq)), an increase in oxidation state, which means it loses electrons and is oxidized. B. reduced: A substance that is reduced is the oxidizing agent, not the reducing agent. Hydrogen ions (H+) are reduced in this reaction (from +1 to 0). C. a metal: While magnesium is a metal, being a metal is its physical and chemical classification, not the reason it acts as a reducing agent in the context of a specific redox reaction. The reason is rooted in the change in its oxidation state. D. a solid: The state of magnesium (solid) is a physical property. The chemical reason it acts as a reducing agent is its tendency to lose electrons (get oxidized) during the reaction. :. The correct answer is oxidized - option A

Dissolving sodium chloride in water is a physical change because the chemical composition of the salt (NaCl) and water (H₂O) does not change. The salt ions simply disperse within the water molecules. The original substances can be recovered by physical means, such as evaporating the water, which leaves the solid salt behind. Hence, no new substance is formed, and it is easily reversible. A. addition of water to calcium oxide is a chemical change. Calcium oxide (quicklime) reacts vigorously with water in an exothermic reaction to form a new substance, calcium hydroxide. B. corrosion of iron is a chemical change. Iron reacts with oxygen and moisture in the air to form iron oxide (rust), which is a new substance with different properties from the original iron. D. burning of charcoal is a chemical change. Burning (combustion) involves the reaction of charcoal (primarily carbon) with oxygen to produce new substances, such as carbon dioxide and possibly carbon monoxide, which cannot be easily reversed to get the original charcoal back. The correct option is C. dissolving sodium chloride in water.

The main components of air are nitrogen (~78%), oxygen (~21%), noble gases (~0.9%), carbon dioxide (~0.04%), and variable amounts of water vapour. After these steps, all oxygen, carbon dioxide, and water vapor are removed, leaving nitrogen and the noble gases (predominantly argon) as the remaining unabsorbed components. Recall that Air is a mixture of gases. These gases comprises mainly nitrogen, oxygen, carbon(IV) oxide, noble gases, and water vapour. Alkaline pyrogallol is used to absorb oxygen from the air. Potash (potassium carbonate, though potassium hydroxide is more common in this context) absorbs carbon(IV)oxide (carbon dioxide). Fused calcium chloride is a drying agent used to absorb water vapor (moisture). After passing the air sample through all three substances, the components of air that are left unabsorbed are the chemically inert noble gases (like argon, neon, etc.) and the relatively unreactive nitrogen, which together make up the bulk of the remaining gas. Correct answer is noble gases and nitrogen - Option C

The electron configuration provided is 1s² 2s² 2p⁶ 3s² 3p⁵. The outermost energy level (principal quantum number n = 3, or the third shell) contains the valence electrons. To find the number of valence electrons, the electrons in the 3s and 3p sub-shells are summed: 2 + 5 = 7 valence electrons. Elements with 7 valence electrons in their outermost shell belong to Group 7 (or Group 17 in modern IUPAC notation) of the periodic table, known as the halogens. The element with this configuration is chlorine (atomic number 17). The correct option is A - Group 7