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Test Observation Inference (i) C + 10cm\(^3\) of water Dissolves forming a solution C is soluble in water (ii) Solution C + NaOH\(_{(aq)}\) in drops and excess White precipitate which is insoluble in excess Ca\(^{2+}\) is present iii) Solution C + HNO\(_{3(aq)}\) + AgNO\(_{3(aq)}\) + NH\(_{3(aq)}\) in excess No visible reaction. A white precipitate formed. The precipitate is soluble Cl\(^{-1}\) present Cl\(^{-}\) confirmed (iv) D + NaHCO\(_3\) Effervescence occurs, colourless gas evolved which turns lime water milky D is an organic acid or an alkanoic acid

Titration/Burette Reading Rough(cm\(^3\)) 1st Titre (cm\(^3\)) 2nd Titre (cm\(^3\) 3rd Titre (cm\(^3\)) Final Reading 22.80 22.70 32.70 22.70 Initial Reading 0.00 0.00 10.00 0.00 Volume of acid used 22.00 22.70 22.70 22.70 Volume of pipette used = 25.00 cm\(^3\) Average volume of acid = \(\frac{22.70 + 22.70 +22.70}{3}\) = \(\frac{68.10}{3}\) = 22.70 cm\(^3\) (b)(i) Concentration of A in mol/dm\(^3\) = \(\frac{\text{conc. of A in g/dm}^3}{\text{Molar mass of A}}\) Molar mass of H\(_2\)SO\(_{4(aq)}\) = 1 x 2 + 32 x 16 x 4 = 98 g/mol Conc. of A in mol/dm\(^3\) = \(\frac{4.9}{98}\) = 0.05 mol/dm\(^3\) (ii) H\(_2\)SO\(_4\) + Na\(_2\)CO\(_{3(aq)}\) \(\to\) Na\(_2\)SO\(_{4(aq)}\) + H\(_2\)O\(_{(l)}\) + CO\(_{2(g)}\) \(\frac{C_AV_A}{C_BV_B} = \frac{\text{Mole ratio of acid}}{\text{Molar ration of base}}\) \(\frac{0.05 \times 22.7}{C_B \times 25} = \frac{1}{1}\) C\(_B\) = \(\frac{0.05 \times 22.7 \times 1}{25 \times 1}\) = 0.0454 C\(_B\) = 0.05 3 S.F C\(_B\) = 0.05 mol/dm\(^3\) (iii) Moles of B = \(\frac{ \text{conc. of B in mol/dm}^3 \times Volume of B}{1000}\) \(\frac{0.05 \times 500}{1000}\) = 0.025 moles Molar mass of Na\(_2\)SO\(_4\) = 2 x 23 + 32 + 16 x 4 = 142 g/mol 1 mole of B formed 142g of Na\(_2\)SO\(_4\) 0.025 moles of B will form \(\frac{0.025 \times 142}{1}\) = 3.55 g (iv) 1 mole of B produces 22.4 dm\(^3\) of CO\(_2\) at s.t.p. 0.025 mole of B will produce 0.025 x 22.4 = 0.56 dm\(^3\) of CO\(_2\) at s.t.p. C is CaCl\(_2\), D is CH\(_3\)COOH or Benzoic acid

The IUPAC nomenclature for the hydrocarbon is 3-methylbut-1-ene. First, identify the longest C- chain. The longest 4 Carbon atoms → But-1-ene (because of the double bond on C-1 which depicts an ethene) Secondly, the substituent functional group methyl CH\(_3\) → 3-methyl (because the methyl is on C-3 with reference from where the double bond counts from) Lastly, add up step 2 and 1 → 3-methyl but-1-ene.

"Perceptive" refers to the ability to perceive or understand things quickly and accurately, often through observation or insight. In the context of the sentence, Sikemi's observant nature suggests that she is perceptive, noticing details and understanding situations well.

"Crucial" means extremely important or essential. It is similar to the idea of playing a vital role in the development of Africa.

"Authentic" in this context implies genuine or true to life, similar to being realistic. It suggests that Emeka's painting closely resembles reality and is not artificial or exaggerated.

The word "courteously" means in a polite, considerate, or mannerly way. In the context of the sentence, Ade is showing courtesy by standing back and letting his teacher go through the door first. Therefore, the word "polite" in option B is the closest in meaning to "courteously." Both words convey the idea of behaving with good manners and showing respect.

The word "poverty" refers to the state of being extremely poor, lacking basic necessities or financial resources. Option B, "want," is the option nearest in meaning. "Want" can be used as a synonym for poverty, indicating a state of lacking material possessions or financial means. Options A, C, and D do not accurately capture the meaning of living in poverty. Option A, "instability," generally refers to a lack of stability, option C, "difficulty," is more about challenges in general, and option D, "the slums," refers specifically to impoverished areas rather than the state of poverty itself.

"Accountability" and "responsibility" are closely related concepts that both involve being answerable for one's actions or duties. In the context of the sentence, accountability is described as a desirable quality, indicating the importance of being responsible and accountable for one's decisions and actions, especially for a politician.

"Prevalent" means widespread or commonly occurring.

fateful adjective fate·ful \ˈfāt-fəl\ Simple Definition of fateful : having important results : producing a serious and usually bad result Synonyms = calamitous, cataclysmal (or cataclysmic), catastrophic, damning, destructive, disastrous, fatal, ruinous, unfortunate

"Superficial" typically refers to something that is on the surface or not deep, so an "external" wound, which is on the outside of the body is the nearest in meaning.

To fizzle out means to gradually end, often in a disappointing or weak way. It’s like a firework that starts with a promising spark but then fades away without much impact. For instance, if someone’s enthusiasm for a project or reform wanes after an initial burst of energy, we can say it fizzled out. "Fizzled out" can also imply a disappointing or unsatisfactory end, such as giving up or surrendering in a disappointing manner.

"Vehement" means showing strong feelings or passion, often characterised by intensity or insistence. Therefore, describing Mfon as a man of vehement character implies that he is strong-willed, determined, and insistent in his actions or beliefs.

"Lively" typically describes someone or something full of energy, active or spirited. Similarly, "frisky" suggests liveliness, playfulness or being full of vigour.