1. D EQUATION 4 D REACTION IS:

H2SO4(aq) + 2NaOH –> Na2SO4 + 2H2O.

A. Table of value: burrete readn: rough/1st/ 2nd/3rd

final: 24.00/24.30/29.30/34.30

initial: 0.00/0.00/5.00/10.00

vol: 24.00/24.30/24.30/24.30.

Note: rough, 1st, 2nd, 3rd titre are all in (cm3).

Average vol of acid used = 24.30 + 24.30 + 24.30/3 = 72.9/3 = 24.30

Bi. A contains 0.125mol/dm3 of H2SO4 i.e 0.125 in 1000cm3 of H2SO4. X = 24.30 * 0.125/ 1000 = 0.00303 =0.003mol/dm3

ii. CaVa/CbVb = Na/Nb 0.125 * 24.30/Cb * 25 = 1/2 Cb = 6.075/25 = 0.243 = 0.24mol/dm3

iii. B contains Xgdm3 of NaOH, M.Mof NaOH = 40g Mass conc = mole conc * molar mass = 0.243 * 40 = 9.72g.

2. Salt analysis: a. Test: Xn + distlilled H2O. Observ: white ppt. Colourless sol observed. Inferenc: soluble salt

i. Test: filterate + BaCl2 + dil. HCl in excess Observ: white ppt formed. Ppt insoluble Inference: SO4^2-, SO3^2-, CO3^2- presnt.

2. Salt analysis contd:

ii. Test: residue + dil. HCl.

Observ: effervescence gas evolved. An odourless gas. Deep blue ppt. Inference: Cu^2+ presnt

iii. Test: filterate + HNO3 + AgNO3 + NH3. Observ: no visible reaction. White ppt formed. Ppt dissolved in excess NH3(aq).

Inference: Cl- present. Cl- confirmed bi. Test: filterate + BaCl2 + Dil. HCl. Observ: white ppt remained insoluble.

Inferenc: CO3^2-, SO4^2- presnt

ii. Test: A portion of bi + NaOH solutn in drop then in exces Observ: A light blue ppt insoluble in exces of NaOH sol.

Inferenc: Cu^2+ presnt.

Note: it must b in tabular i.e test/observ/inf.

2c obser) colourless odourles gas evolve which turn lime water milky.

2c infer) the gas is CO2 from CO2-3

2a obser) x is partially soluble in water to form white filtrate and blue residue

.2a infer) x is a mixture of solubluble and insoluble salts

2bii) white precipitate dissolve. 2bii) Cl- confirmed

2ci obser) blue precipitate remain insoluble.

2ci infer) Cu2+ present.

3a)orange to green

3b)i)liebig condenser

ii)hoffmans voltametre

iii)restort stand

iv)spatulla

v)seperatibg funel

vi)evaporating dish

.

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