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If the salt is made up of the conjugate base of a strong acid and the conjugate acid of a weak base, then the salt is acidic.KHSO4 is made up of a conjugate base of a strong acid (H2SO4), hence, it is an acidic salt. The correct option is C

The brown gas produced is nitrogen(iv)oxide (NO2), a common product of nitric acid reactions. Also, note that Nitric acid is a strong oxidizing agent, meaning it readily accepts electrons from other substances. Wood shavings are primarily composed of cellulose, a complex carbohydrate. The reaction between concentrated nitric acid and cellulose involves the oxidation of cellulose by nitric acid, resulting in the formation of nitrogen dioxide(brown gas) and other products. This is an oxidation-reduction reaction (Redox reactions). The correct answer is option A

Chemical equilibrium is attained whenever the concentration of reactants on the Left hand side and the concentration of the products on the left hand side remain unchanged or constant. Which means the effect of the changes brought on the system in equilibrium has been cancelled according to Le Chatelier's principle. The correct answer is option C

The metallic rod has a small surface area relative to the same mass of finely grounded metal. This means that more particles of the finely grounded metal will be in contact with air than the metallic rod. As a result, there can be more successful collisions per unit time and the reaction of finely grounded metal is faster. Increasing the surface area of the reactants increases the rate of the reaction. Thus, option B is the correct answer.

The tendency of a metal displacing the other is based on their position in the electrochemicals series. The metal above the other will displace the lower. Magnesium, Aluminium and Zinc are all above Copper, hence, by default, they should all displace Copper, but the option says Alumimium ion and Zinc ion, not Aluminium metal and Zinc metal. It is only Magnesium that is in metallic form not ion.Therefore, the answer is Magnesium. Option B You can make reference to your electrochemical series.

Cr2O72- + 14H+ + xe- → 2Cr3+ + 7H2O Consider the total ionic substances on the LHS and that on the RHS LHS= -2 (from Cr2O7 2-) + 14 (from 14H+) +x = -2 +14 + x RHS= 2 x +3 (from 2Cr3+) = +6 Equate LHS and RHS -2 + 14 + x = +6 (ensure both values on the LHS and RHS are equal) +12 + x = +6 x = 6 -12 = -6 (minus because its an electron) thus, x = 6. Option B is the correct answer (See also image attached)

Calculating the Oxidation number of all the options, B is the correct answer. Hydrogen has oxidation state of +1 in that compound H2S equated to 0. i.e H2S = 0 2H + S = 0 2(+1) + S = 0 +2 + S = 0 S = 0 -2 S = - 2. - Option B

When an iron nail is placed in a solution of copper (ll) tetraoxosulphate (VI), the nail is covered with a brown deposit of copper, which means it's solid, and green FeSO4 (Fe2+) is also produced. Perusing the equations in the given options, it's only in option D we have Cu solid as one of it's product. Option D is the correct answer.

0.10 mol \(dm^{-3}\) NaCI conducts electricity better than 0.10 mol \(dm^{-3}\) \(CH_3COOH\) because the solution of NaCI contains more ions. When an ionic compound like NaCI dissolves in water, it dissociates into its component ions, \(Na^+\) and \(Cl^{-}\)

During the electrolysis of an aqueous solution of CuSO4 in the presence of Cu electrodes, copper metal will be deposited at cathode.

Chromatography is used for quality control in the food industry, by separating and analyzing additives, vitamins, preservatives, proteins, and amino acids. It can also separate and detect contaminants such as aflatoxin, a cancer-causing chemical produced by a mold on peanuts.

This is referred to the hydrogenation of alkynes.Hydrogenation of alkynes is a reaction that replaces one or more of an alkyne's pi bonds with hydrogen atoms. This process is a step-by-step reaction that typically converts a triple bond into a double bond, and then a double bond into a single bond. This is applicable to option D because, you'll be needing 4 atoms of Hydrogen as shown in the question, to break the tripple bond, and convert first to double bond, and then to a single bond.

The compound C8H18 is a saturated Hydrocarbon i.e Alkane. Alkanes are known for their ability to undergo substitution, combustion and cracking(breaking down of larger molecules of HC into smaller HCs) reactions, while addition reaction is peculiar to Unsaturated hydrocarbons such as alkenes and alkynes. Option D is the correct answer

Both compounds are alkanols (presence of the -OH group). i.e Propanol and Butan-2-ol respectively. Thus they have the same general molecular formular as CnH2n+1 OH. The correct answer is option C

Sucrose needs to be hydrolyzed before it can show reducing properties because sucrose is a non-reducing sugar, which means it cannot reduce other compounds. Sucrose is a non-reducing sugar because it doesn't have a free aldehyde or ketone group. Thus, hydrolysis of sucrose is necessary in order to break the glycosidic bond between glucose and fructose(Sucrose) and convert them to free sugars that can show reducing properties. The correct answer is option C.