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When you dissolve ammonium chloride crystals in water (H\(_2\)O), the ammonium chloride compound decomposes into its component ions: NH\(_4 ^+\) and Cl\(^-\). The reaction of these ions with water gives an acidic solution.

The reaction rate between a solid and liquid will not be affected by pressure. Pressure majorly affects the reaction rate for gases.

No expanded working has been attached for this question yet. The verified answer is Option C.

Let the oxidation number of Fe in the compound [Fe(CN)\(_6\)]\(^{3-}\) be x. x + 6(-1) = -3 x - 6 = -3; x = -3 + 6 x = +3

In the reaction, a complex hydrocarbon is broken down into two simpler hydrocarbons. This is cracking.

Vinegar is a product from fermentation. It can be gotten from the fermentation of ethanol.

An alkene reacts with conc. H\(_2\)SO\(_4\) to yield an alkyl hydrogen tetraoxosulphate (VI). The compound formed undergoes hydrolysis when boiled with water to yield an alcohol.

No expanded working has been attached for this question yet. The verified answer is Option C.

The brewing of beer has to do with fermentation.

No expanded working has been attached for this question yet. The verified answer is Option C.

No expanded working has been attached for this question yet. The verified answer is Option A.

Brass is an alloy made from copper and zinc. Unlike pure metals, most alloys do not have a single melting point, but a melting range in which the material is a mixture of solid and liquid phases.

Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons—gases formerly found in aerosol spray cans and refrigerants—are released into the atmosphere

ROUGH (cm\(^3\)) 1st Titration (cm\(^3\)) 2nd Titration (cm\(^3\) Initial Burette Reading 27.00 49.50 36.00 Initial Burette Reading 01.00 26.00 12.40 Vol. of Acid Used(cm\(^3\)) 26.00 23.50 23.60 Average Titre = \(\frac{23.50 + 23.60}{2}\) = 23.55cm\(^{3}\) (b)(i) Concentration of B in moldm\(^{-3}\) Molar mass of NaOH = 23 + 16 + 1 = 40g mol\(^{-1}) concentration of B = \(\frac{3.90}{40}\) = 0.0975 mol dm\(^{-1}\) (ii) concentration of BAin mol dm\(^{-3}\) \(\frac{C_AV_A}{C_BV_B}\) = \(\frac{1}{2}\) C\(_A = \frac{C_BV_B}{2V_A}\) C\(_A\) = \(\frac{0.975 \times 25}{2 \times 23.55}\) = 0.0518 mol dm\(^{-3}\) (ii) Molar mass of H\(_2\)Y Molar mas of H\(_2\)Y = \(\frac{6.22}{0.0518}\) = 120 gmol\(^{-1}\) (c)(i) Less than 7 (ii) Greater than 7 [C = (NH\(_4\))\(_2\)SO\(_{4(aq)}\); D = FeCl\(_{3(aq)}\)

(a)(i) Diffusion is the movement of particles from the region of higher concentration to the region of lower concentration (ii) Charles' Law states that the volume of a given mass of gas is directly proportional to its absolute temperature at a constant pressure. (iii) OR (iv) \(\frac{V_1}{T_1} = \frac{V_2}{T_2}\) \(T_2 = \frac{T_1V_2}{V_1}\) \(T_2 = \frac{300 \times 300}{150} = 600k\) (v)(i) Solid < liquid < gas / solid, liquid, gas (ii) Gas < liquid < Solid / gas, liquid, solid b)(i) In a reversible reaction at equilibrium, if any will of the factors affecting the equilibrium is altered, the position of equilibrium will change so as to annul the effect of the change (ii) Oxide I % of O\(_2\) = 11.1 % % by mass of metal = 88.9% 11.1 of O\(_2\) combined with 88.9 of metal 100 of O\(_2\) = \(\frac{100}{88.9}\) = 800.9g Oxide II % of O\(_2\) = 20% % by mass of metal = 80% 20 of O\(_2\) combined with 80 of metal 100 of O\(_2\) = \(\frac{100}{ 80}\) = 400g Ratio of metal in both oxides = 800. 9 : 400 2 : 1 (c)(i) Add water to mixture A, B and C and stir. — C dissolves — Filter to obtain C as filtrate and A and B as residue — Heat residue until melted. — Separate by simple distillation — Evaporate filtrate to dryness to obtain solid C — Pure A is collected at 117^\circC and pure B at 160^\circC (ii) Mass of mixture = 25.25g Mass A + B = 7.52g + 8.48g = 16.00g Mass of C = 25.25 - 16.00g = 9.25g % of C in mixture = \(\frac{9.25}{25.25}\) x 100 = 36.6%