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(a)(i) Reactance s the opposition in ohms to the alternating current by an inductor, a capacitor or both. (ii) Impedance is the total opposition is ohms to the alternating current by a combination of resistor as well as a capacitor or an inductor. (b)(i) Resonant frequency fo is to frequency at which the current in the circuit has a maximum value. fo = \(\frac{1}{2 \pi LC}\) (ii) This means that the root mean square value of the voltage is 230v. The actual voltage lies between Vo and -Vo where the voltage amplitude or peak voltage Vo. (c)(i) \(V^2 = V^2_R + (V_L - V_C)^2; 240^2 = 140^2 + (50 - v_c)^2\); 50 - \(V_c = 194.9\) \(V_c = 244.9v\) (ii) X\(_c = \frac{1}{2 \pi fc} = \frac{V}{1} = \frac{1}{2 \pi \times 50 \times c} = \frac{244.9}{10}\) C = \(\frac{10}{2 \pi \times 50 \times 244.9} = 129.97 \mu F\) (iii) \(X_L = 2 \pi fL = \frac{v}{l}; 2 \pi \times 50 \times L = \frac{50}{10}\) L = \(\frac{50}{100x}\) = 0.01159Hz (d)

a)(i) Nuclear fission is a nuclear reaction in which a heavy nucleus is split into different lighter nuclei emitting neutrons with the release of a large amount of energy. (ii) Nuclear fusion is a nuclear reaction between two light nuclei at high temperatures formic a heavier nucleus with the release of a large amount of energy. (b)(i) Applications of atomic energy are: - for the production of nuclear weapons for warfare - in the generation of electric power - for health diagnosis and radiotherapy - to detect leakages. In underground pipes carrying oils or gases. (ii) Half life is the time required for radioactive substance to decay to half of its original quantity. (iii) T = \(\frac{0.693}{\lambda}\) (c)(i) \(^{226}_{88} X \) ---> \(^{222}_{88} Y + ^4_2He\) By the emission of \(\alpha\) the mass number of X decreases by 4 the atomic number by 2 to give daughter nucleus Y (ii) \(^{222}_{86} Y \) ---> \(^{222}_{87} Z + ^0_{-1} e\) By the emission of \(\beta\) particle the mass number of Y is unchanged while the atomic number of Y is unchanged while the atomic number is increased by 1. (iii) \(^{226}_{87} Z \) ---> \(^{222}_{87} Z + ^0_0\gamma\) By emission of \(\gamma\) radiation, the mass and atomic number of Z remain unchanged.

K- (31.91%), Mole = 31.91/39 =0.8182 Cl-(28.93%), Mole = 28.93/35.5 = 0.815 O-(39.16%), Mole = 39.6/16 = 2.448 K = 0.8182/0.815 = 1 Cl = 0.815/0.815 = 1 O = 2.448/0.815 = 3

The empirical formula is the simplest whole number ratio of the number of atoms of each element in a substance. In the case of ethanoic acid, the ratio of atoms is 1:2:1, as shown by the empirical formula CH\(_2\)O. The molecular formula for ethanoic acid is C\(_2\)H\(_4\)O\(_2\).

Trichloromethane (Chloroform) being in smaller quantity and ethanol being in large quantity means trichloromethane is the impurity while the ethanol is the pure substance. As we know, impurities in pure substances tend to increase their boiling point. Consequently, if the boiling point of ethanol (pure substance) is 78\(^0\)C, with the introduction of impurity (trichloromethane), the boiling point will increase from 78\(^0\)C. Among the options, the only temperature range that has a boiling point higher than 78\(^0\)C is option C (82 - 84\(^0\)C).

Chromatography is a laboratory technique for the separation of a mixture into its components. A mixture is dissolved in a mobile phase, which is a liquid or gas that flows through a stationary phase, which is a solid or liquid. The components of the mixture separate as they travel through the stationary phase because they have different affinities for it. The chromatography separation of ink is based on the ability of the components to move at different speeds in the column.

Le Chatelier's principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium shifts to counteract the change to reestablish an equilibrium. For the backward reaction to be favoured(LHS) , the concentration of one of the reactants must be reduced. i.e either E or F must be reduced. However, from the option, option C happens to be the one that fits in, as E is the only reactant reduced.

If delta G standard is zero, the system is at equilibrium at standard conditions. This time the rate of the forward and reverse reaction is the same, and the system is at equilibrium.

First, calculate the total number of number of moles of gaseous species only, on both sides. i.e 1 mole on the LHS while 2 moles on RHS. An increase in pressure will favour the side with the lesser value of the total number of moles while a decrease in pressure will favour the side with the higher number of moles i.e the RHS. Hence,increasing the yield of PCl\(_3\).

A reaction between Iron (iii) chloride and Hydrogen sulphide leads to the reaction 2FeCl\(_3\)(aq) + H\(_2\)S(g) → 2FeCl\(_2\)(aq) + 2HCl(aq) + S(s) The colour change is from REDDISH BROWN to PALE GREEN.

Above is the Arrhenius equation. It is a relationship between speed and activation energy.

When sodium hydroxide dissolves in water, the process is exothermic because the breaking of the ionic bonds in sodium hydroxide releases heat.

Sulphur atom in Cu\(_2\)S is - 2. Thus, Cu\(_2\)S = 0 2Cu + S = 0 2Cu + (-2) = 0 2Cu = 2 \(\frac{2Cu}{2}\) = \(\frac{2}{2}\) Cu = +1 On the RHS, Cu atom has an oxidation state of 0. Therefore, there is a change in oxidation number of Copper from +1 to 0

The products of the electrolysis of dilute sodium hydroxide using platinum electrodes are hydrogen H\(_2\) at the cathode and oxygen (O\(_2\) at the anode. This is because the reduction and oxidation of water occurs to produce hydrogen at the cathode and oxygen at the anode.

At 20oC 0.34 mol/dm of the salt dissolve = 0.34 * 101 = 34.34gm Of the salt dissolved. ∴ 34.34gm dissolve is 1,000cm3 If only 250 cm3 is the required mass X = (250/1000) * 34.34 = 8.555gm If only 3.40gm of the salt dissolved ,the solution is unsaturated