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(a)i. An acid is any compound which in a chemical reaction is able to attach itself to an unshared pair of electrons in another molecule-a base, to form a new compound ii. - AlCl3 - BF3 - BeF2 - H+ - K+ (b). It is the addition of NaCl to the reaction mixture in soap production to facilitate the precipitation of soap from the mixture (c) Reagent -- AgNO3 in NH3(aq) / Ammonical silver trioxonitrate condition-- heat (d) - It is the fraction of a given isotope in amixture of isotopes of the same element - The % of an isotope with a specific atomic mass found in a naturally occuring sample of an element. (e)i. Because the element is - Unreactive - Stable - A noble gas - Inert - Completely filled outermost shell ii. Because of weak forces between the molecules hence not much heat is needed to break the forces (f) - (Conc) HNO3 produces brown fumes (of NO2) when copper tunings are added to it/copper (II) salt is added but H2SO4 will not react with the copper tuning/Copper (II) salt - When Conc. H2SO4 is added to sugar it chars the sugar but Conc. HNO3 will not. - Add BaCl2 solution to each acid white precipitate indicates H2SO4 no precipitate indicates HNO3 (g) Electrochemical cell Electrolytic cell anode is negative/cathode is positive anode is positive/cathode is negative reaction is spontaneous non-spontaneous chemical energy is converted to electrical energy electrical energy is converted to chemical energy current is generated from within the cell current is generated from external source/battery the two half cells are in separate containers and connected by a salt bridge the two half cells are in the same container (h) Ionization energy decreases down group 1 elements, the lower the ionization energy, the easier to loose an electron hence the higher the reactive of the elements (i) Molecular formula shows the actual number of atoms of each element in a molecule (j) NH3 will deviate more because it has a larger volume and also it has a stronger intermolecular forces

(a)i. Temperature: 350-5000C/high temperature Pressure: 150-1000 atm/high pressure Catalyst: (Finely divided) Iron ii. Rate of the reaction increases as particles are closer together/more particles per unit volume. There are more collisions per seconds/collisions are more often (b)i. 4NO2 + O2 + 2H2O -----> 4HNO3 ii. 2NO2 + 2H2O -----> HNO3 + HNO2 A misture of two acids will be produced iii. 4HNO3(aq) → 4NO2 + O2 + 2H2O i. - Oxygen is neutral while NO2 is acidic ii. - NO2 is soluble while O2 is sparingly soluble in water iii. - O2 reacts with CO to form CO2 while NO2 reacts with CO to form a mixture of N2 and CO2 (c)i. Sulphur(IV) oxide Sulphur (VI) oxide ii. SO2(g) + H2O(l) ---->H2SO3(aq) SO3(g) + H2O(l) ---->H2SO4(aq) (d)i. - calcium oxide - quick lime b. - Limestone - Quick lime - Calcium trioxocarbonat(IV) - Calcium oxide c. - Calcium chloride - Calcium tetraoxosulphate (VI) - Calcium hydrogen trioxocarbonate (IV) d. Calcium tetraoxosulphate (VI) (dihydrate)

(a)i. Its colour darkens from pale yellow to amber colour while its crystals become needle-like and at 119oC it begins to melt. ii. The solution turns green, bubbles of colourless gas rise from the bottom of the mixture, but brown fumes of NO2 are produced and the solutions later turns blue. (b)i - SO2 - CO2 - CO - NO2 - H2S ii. Methane iii. - Contamination of soil - Soil erosion - Contamination of ground water - Loss of biodiversity - Formation of sink holes iv. Because of the large surface area and the higher the area the faster the rate of reaction. v. Coke (c)i. The sample is added to anhydrous copper (II) tetraoxosulphate (VI) when it turns from white to blue confirms the presence of water/sample is added to anhydrous cobalt chloride/cobalt chloride paper when it turns from blue to pink indicates the presence of water. ii(a) It softens temporary hard water (b) To remove permanent hardness/soften hard water iii. - Ca(HCO3)2 ---heat--->CaCO3 + CO2 + H2O + H2O or Mg(HCO3)2 ---heat--->MgCO3 + CO2 + H2O + H2O

Ethanol fermentation, also called alcoholic fermentation, is a biological process which converts sugars such as glucose, fructose, and sucrose into cellular energy, producing ethanol and carbon dioxide as by-products

Maltose is produced by the enzymatic hydrolysis of starch (a homopolysaccharide) catalyzed by the enzyme amylase.

Soaps cannot be used in acidic condition because they lose their cleansing effect due to the formation of long chain fatty acids

Condensation polymers are any kind of polymers whose process of polymerization involves a condensation reaction.

AlCl3 → Al3+ + 3Cl- At cathode: Al3+ + 3e- → Al 3 mole of electrons corresponds 3 F charge So, required charge =3 F

The addition of bromine to most alkenes is so fast that when bromine is added dropwise to a solution of the alkene the red bromine color disappears almost immediately. In fact, this discharge of color is a useful qualitative test for alkenes.

An alkene reacts with conc. H2SO4 to yield an alkyl hydrogen tetraoxosulphate (VI). The compound formed undergoes hydrolysis when boiled with water to yield an alcohol.

The standard hydrogen electrode consists of hydrogen gas at 25oC

Data obtained from the question M = 60 g O = 24 g Empirical formula =? How to determine the empirical formula Divide by their molar mass M = 60\div120 = 0.5 O = 24 \div16 = 1.5 Divide by the smallest M = 0.5\div0.5 = 1 O = 1.5 \div0.5 = 3 Thus, the empirical formula of the oxide is MO₃

Oxygen is produced at the anode and hydrogen is produced at the cathode in dilute NaCl

Q =It t = 60 * 60=3600 I = 0.20 Q=0.20 * 3600 Q= 720C

HOCl is unstable and decomposes to release oxygen which oxidizes the dye to form a colourless compound.